The factored quadratic expression of 2x²+7x+3 as the the product of two linear binomials is (2x+1)(x+3)
To factor trinomials with a leading coefficient greater than 1, follow these steps
Multiply the coefficient of the leading term by the constant term.
Find two factors of the product from step 1 that add up to the coefficient of the middle term.
Rewrite the middle term using the two factors found in step 2.
Factor by grouping the first two terms and the last two terms.
Factor out the common factor.
Let's use the example 2x²+7x+3 to demonstrate these steps
2 x 3 = 6
Find two factors of 6 that add up to 7: 6 and 1
Rewrite the middle term as 6x + 1x
Factor by grouping
2x² + 6x + 1x + 3
2x(x + 3) + 1(x + 3)
Factor out the common factor
(2x + 1)(x + 3)
Therefore, 2x²+7x+3 can be factored as (2x + 1)(x + 3).
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At a distance of 6 meters, a person with average vision is able to clearly read letters 1.0 cm high.Approximately how large do the letters appear on the retina? (Assume that the retina is 1.7 cm from the lens.)
The size of the letters appear on the retina is 0.00289 cm
Given data:
To determine the size of the letters on the retina, use the concept of angular size and the relationship between object size, distance, and angular size.
Angular size is the measure of the angle subtended by an object as seen from a particular point, in this case, the eye.
Angular size = Object size / Distance
Object size = 1.0 cm
Distance = 6 meters
Angular size = 1.0 cm / 6 meters
To convert the distance to centimeters, multiply by 100:
Angular size = 1.0 cm / (6 meters * 100 cm/meter)
Angular size = 1.0 cm / 600 cm
Angular size = 0.0017 radians
The angular size of the letters is 0.0017 radians.
Now, to determine the size of the letters on the retina, calculate the linear size on the retina using the angular size and the distance from the lens to the retina.
Linear size on retina = Angular size * Distance from lens to retina
Angular size = 0.0017 radians
Distance from lens to retina = 1.7 cm
Linear size on retina = 0.0017 radians * 1.7 cm
Linear size on retina ≈ 0.00289 cm
Hence, the letters appear to be approximately 0.00289 cm in size on the retina.
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what are the multiples of 3
Answer:
3,6,9,12,etc
Step-by-step explanation:
In math, a multiple is the product of any quantity and an integer. In other words, for the quantities a and b, we say that b is a multiple of a if b = na for some integer n, which is called the multiplier. If a is not zero, this is equivalent to saying that b/a is an integer.
Determine the probability of precipitation (PoP) using the formula below and the following
PoP = (C * A) * 100 percent
Where C is the confidence that precipitation will occurs somewhere in the forecasted area, and A equals the percentage of the area that will receive measured precipitation if it occurs.
a. A forecaster expresses confidence that there is an 80 percent chance of precipitation in the forecasted area, and it is expected to produce measurable precipitation over 90 percent of the area.
b. A forecaster expresses confidence that there is a 20 percent chance of precipitation in the forecasted area, and it is expected to produce measurable precipitation over 10 percent of the area.
The correct answer is a) the probability of precipitation is 72%. and b) the probability of precipitation is 2%.
The given formula to determine the probability of precipitation (PoP) is PoP = (C * A) * 100 percent where C represents the confidence that precipitation will occur somewhere in the forecasted area and A represents the percentage of the area that will receive measured precipitation if it occurs.
(a) If a forecaster expresses confidence that there is an 80% chance of precipitation in the forecasted area, and it is expected to produce measurable precipitation over 90% of the area, then the probability of precipitation is given as follows: PoP = (C * A) * 100 per cent C = 80%A = 90%PoP = (80% * 90%) * 100%
PoP = 72%.
Therefore, the probability of precipitation is 72%.
(b) If a forecaster expresses confidence that there is a 20% chance of precipitation in the forecasted area, and it is expected to produce measurable precipitation over 10% of the area, then the probability of precipitation is given as follows: PoP = (C * A) * 100 per cent C = 20%A = 10%PoP = (20% * 10%) * 100%PoP = 2%
Therefore, the probability of precipitation is 2%.
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Homework Progress
579 Marks
Aplo of sand has a weight of 90 kg.
The sand is put into a small bag, a medium bag and a large bag
in the ratio 2:3:7.
Work out the weight of sand in each bag.
Answer:
77
Step-by-step explanation:
2:3:7.
what is the difference between descriptive statistics and inferential statistics?
A data set's attributes are enumerated through descriptive statistics. You can use inferential statistics to test a hypothesis or determine whether your data can be applied to a larger population.
Descriptive statistics concentrate on describing the features of a dataset that are readily evident (a population or sample). In contrast, inferential statistics concentrate on drawing conclusions or generalisations from a sample of data in a larger dataset.
The information from a research sample is described and condensed using descriptive statistics. We can draw conclusions about the larger population from which we drew our sample using inferential statistics.
The area of statistics known as descriptive statistics is focused on providing a description of the population being studied. A type of statistics known as inferential statistics concentrates on inferring information about the population from sample analysis and observation.
Hence we get the required answer.
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help me solve this please
Answer:
(6, 20) (8, 42)
Find the gradient:
(6 = x1, 20 = y1)
(8 = x2, 42 = y2)
Formula = m = y2 - y1 divided by x2 - x1
m = 42 - 20 divided by 8-6
m = 22/2
m = 11/1 which is the same as 11
Find the y-intercept:
Then, take one of the coordinates above. In this case, I'll take (6, 20).
y = mx + cThen we replace y and x from the coordinates.
20 = 11(6) + c66 + c = 20c = 20 - 66c = -46y = 11x - 46
For a unity feedback system with feedforward transfer function as
G(s)= 2+2x+10
the root locus is sketched as follows.
-plane
ba
0
R
-4
find the values of a, b, and c on the real axis and d on the imaginary axis (Note: For negative values, the sign is already inserted, you just need to insert the value).
a
b-
CF
d=
The final answer is: a = -6, b+ = √3/2, c = -3, and d = ∞
Given the unity feedback system with feedforward transfer function as G(s)= 2+2s+10 and the root locus is sketched in the -plane as below:
For this system, let's find the values of a, b, c, and d on the real axis and the imaginary axis using the root locus sketch.
The general equation of a straight line in the complex plane can be expressed as:
{}=+ ,
where
: real-axis intercept.
: slope.
For the given root locus plot, the value is 0.382.
The angle of the asymptotes is given as:
θ=×360°±180°
where n is the number of open-loop poles minus the number of open-loop zeros.
Here,
n=2-1
=1.θ
=360°±180°
=±180°
For the locus to intersect the real-axis at =, we have to determine the value of .
This can be determined using the angle condition:
Angle condition:∑=2−1×180°
where is the angle of departure (→∞) or the angle of arrival (→) of the th branch of the root locus.
For the given root locus plot, we have three branches.
Therefore, we will have three angles:
1
=π−π/3
=2π/32
=π+π/3
=4π/33
=−π
In the figure, there are 2 open-loop poles at =−1, and =−5, and no open-loop zeros.
Therefore, the number of branches in the root locus is 2 for this system.
The root locus plot has two branches that terminate on the real-axis at =1 and =2, respectively.
The angle condition gives:
∑
=2−1×180°
=(2×1−1)×180°
=180°.1+2+3
=2π/3+4π/3−π
=2π/3
Then, we have,
=180°−2π/3=60°
Slope (b) of the line joining =−5 and =1 is given by:
=()=tan(60°)=√3x=-(1+2)/2
where 1 and 2 are the values of the two points in the real axis where the root locus intersects the real axis.
=−()=(−5+1)=(−5+1)√3/2
For the line joining =−1 and =2:
Slope (b) of the line joining =−5 and =1 is given by:
=()
=tan(−60°)
=−√3
=−()
=(−1+2)/2
=−(−1+2)√3/2
The transfer function of the given system is:
G(s)=2+2s+10=12/s+5+s
Let's write the transfer function using pole-zero form:
G(s)=12(1+s/6.67)/(1+s/5)/(1+s/1.5)
Now, we can use the breakaway and break-in points of the real-axis segments of the root locus to solve for the real-axis intercepts 1 and 2.
We have:
Breakaway point:
=−(/2)=−(√3/4)
Break-in point:
=−5
Let's compute the value of d (on the imaginary-axis) using the angle asymptotes.
Due to the two poles of the transfer function, the angle asymptotes intersect at:
θa
=180°/(n−z)
=180°/(2−0)
=90°
Therefore, we have,
=±tan(90°−60°)
=±∞
Finally, the values of a, b, c, and d are:
a=-5.99 (The value of a is approximately equal to -6)
+=+√3/2
c=-3.01 (The value of c is approximately equal to -3)
=∞The sign of b is positive as it intersects =1 on the right-hand side of the origin.
Therefore, the final answer is:
a=-6b+=√3/2c=-3d=∞
a = -6, b+ = √3/2, c = -3, and d = ∞
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Convert 6800 microseconds to centiseconds
Answer:
.68 Centiseconds
Step-by-step explanation:
A microsecond is exactly 1 x 10-6 seconds. 1 µs = 0.000,001 s. One millionth of a second.
and a centisecond is exactly 0.01 seconds. One hundredth of a second.
Im not really sure how to explain it. But I hope that I helped.
There are 0.68 Centiseconds in 6800 microseconds.
What is unit conversion?A unit conversion expresses the same property as a different unit of measurement. For instance, time can be expressed in minutes instead of hours, while distance can be converted from miles to kilometres, or feet, or any other measure of length.
Given that, Convert 6800 microseconds to centiseconds
We know that 1 centisecond = 10000 microseconds
Thereforre, 6800 microseconds = 6800/10000 centiseconds
= 0.68 Centiseconds
Hence, There are 0.68 Centiseconds in 6800 microseconds.
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The enrollment for a school in 2010 was 1510 students. In 2020, the enrollment was 860 students. Find and interpret the rate of change in enrollment from 2010 to 2020.
Answer:
Step-by-step explanation:
The rate of change is the slope of the line formed by connecting the two data points:
1. (2010,1510). and [enrollment for a school in 2010 was 1510 students]
2. (2020, 860) [In 2020, the enrollment was 860 students]
Slope is the Rise/Run of the line. Lets go from the first point to the second.
The Rise: (1510 - 860) = 650
The Run: (2020-2010) = 10
The slope, or rate of change, is = 65
The interpretation is that "The enrollment at the school increase by an average of 65 students every year since 2010 until 2020."
easy problem for you guys to solve
In the ΔIJH, the value of the cosec (I) is \(1\frac{9}{56}\).
Given ΔIJH the length of the hypotenuse is 65, the length of the base is 33, and the length of the opposite side is 56.
We have to find the value of the cosec (I).
A function of an arc or angle that is most easily represented in terms of the ratios of pairs of sides of a right-angled triangle, such as the sine, cosine, tangent, cotangent, secant, or cosecant.
We know cosec (I) = hypotenuse / opposite side
Substitute the values
cosec (I) = 65/56
= \(1\frac{9}{56}\)
Hence the value of cosec (I) is \(1\frac{9}{56}\).
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A sales position needs to be filled. There are two candidates available. The first candidate has 10 years of experience and can sell 10 units a week making a $3,000 profit per week for the company. He is asking for $80,000 salary. The second candidate has one year of experience and can sell eight units a week making a $2,400 profit for the company. He is asking for $45,000 salary. What candidate would make the company the most money their first year of employment?.
The candidate that would make the company the most money in their first year of employment is Candidate B
Which candidate would make more money?The amount of profit that a candidate can make for the company is:
= ( Number of weeks in year x Profit per week ) - Salary for the year
We shall assume 48 working weeks in a year.
The amount of money made by Candidate A would be:
= ( 48 x 3, 000 ) - 80, 000
= $64, 000
The amount of money made by Candidate B is:
= ( 48 x 2, 400 ) - 45, 000
= $70, 200
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Complete the grouped relative frequency distribution for the data. Write each relative frequency as a decimal rounded to the nearest hundredth.( note that we are using a class width of 5)
Relative frequency can be defined as the number of times an event occurs divided by the total number of events occurring in a given scenario. The formula is given to be:
\(RF=\frac{f}{n}\)where f is the number of times the data occurred and n is the total number of observations.
We have the frequency of the individual groups as shown below:
\(\begin{gathered} 1\text{ to }5\Rightarrow3 \\ 6\text{ to }10\Rightarrow8 \\ 11\text{ to }15\Rightarrow3 \\ 16\text{ to }20\Rightarrow5 \end{gathered}\)The total number of observations is 19.
Therefore, the relative frequencies are calculated below:
\(\begin{gathered} 1\text{ to }5\Rightarrow\frac{3}{19}=0.16 \\ 6\text{ to }10\Rightarrow\frac{8}{19}=0.42 \\ 11\text{ to }15\Rightarrow\frac{3}{19}=0.16 \\ 16\text{ to }20\Rightarrow\frac{5}{19}=0.26 \end{gathered}\)ANSWER
\(\begin{gathered} 1\text{ to }5\Rightarrow0.16 \\ 6\text{ to }10\Rightarrow0.42 \\ 11\text{ to }15\Rightarrow0.16 \\ 16\text{ to }20\Rightarrow0.26 \end{gathered}\)T
Simplify the following expression: 15 POINTS
5(-9 + 2x) + 6(8 - 9x)
ASAP PLEASE FAST
3-44x
hope that helped if yes give me brainliest and if no draw my attention by hitting the comment section
Solve: 4 In x=2 In 25
Ox=5
O x = 25
O x = 625
•
•
•
• it’s A =5
•
•
•
Second part is
• it’s B =6
Answer:
x = 5Step-by-step explanation:
Solve the equation in steps as below4 ln x = 2 ln 252 ln x = ln 252 ln x = ln 5²2 ln x = 2 ln 5ln x = ln 5x = 5the middle number; put the values in order from lowest to highest, then find the number that is exactly in the middle
emmanuel weighs 150 pounds. about how many hours will it take him to metabolize one standard drink?
Emmanuel weighs 150 pounds. about 2 hours will it take him to metabolize one standard drink
Every hour, the body processes one normal drink. If you have 5 standard drinks, your body will take 5 hours to absorb the alcohol.
In general, the liver can digest one ounce of liquor (or one standard drink) in one hour. If you consume more than this amount of alcohol, your system will get saturated, and the excess alcohol will accumulate in your blood and physiological tissues until it can be metabolized.
It takes your liver around an hour to break down the amount of alcohol in a standard alcoholic drink (one beer, one glass of wine, or one shot).
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5x - (3x + 2) = 8x + 10
Answer:
x=-2
Step-by-step explanation:
5x - (3x + 2) = 8x + 10
5x-3x-2=8x+10 (Distribute to get rid of the parenthesis)
2x-2=8x+10 (Combine like terms)
-2=6x+10 (Subtract 2x from both sides to get the variable on one side)
-12=6x (Subtract 10 from both sides to get closer to isolating the variable)
-2=x (Divide by 6 on both sides to finish isolating the variable_
A linear system yields outputs y
1
(t)=te
−t
and y
2
(t)=0.5e
−t
for inputs x
1
(t)=t and x
2
(t)=u(t), respectively. What is the output for an input x(t)=2u(t)+t ? A. none of the answers B. y(t)=te
−t
+e
−t
y(t)=2te
−t
+e
−t
y(t)=te
−t
+2e
−t
The output for the input by linearity property \(\(x(t) = 2u(t) + t\)\) is \(\(y(t) = te^{-t} + e^{-t}\)\). (Answer: B.\(\(y(t) = te^{-t} + e^{-t}\))\)
Find the output for the input \(x(t) = 2u(t) + t\), we can use the linearity property of the system.
Output\(\(y_1(t) = te^{-t}\)\) for input \(\(x_1(t) = t\)\)
Output \(\(y_2(t) = 0.5e^{-t}\)\) for input \(\(x_2(t) = u(t)\)\)
We can express \(\(x(t) = 2u(t) + t\)\) as a sum of\(\(x_1(t)\) and \(x_2(t)\):\)
\(\(x(t) = x_1(t) + 2x_2(t)\)\)
Using the linearity property, we can find the output \(\(y(t)\) for \(x(t)\):\(y(t) = y_1(t) + 2y_2(t)\)\)
Substituting the given expressions for \(y_1(t)\) and \(y_2(t)\):
\(\(y(t) = te^{-t} + 2(0.5e^{-t})\)\(y(t) = te^{-t} + e^{-t}\)\)
Therefore, the output for the input \(\(x(t) = 2u(t) + t\) is \(y(t) = te^{-t} + e^{-t}\).\)
B. \(\(y(t) = te^{-t} + e^{-t}\)\)
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22.45=x+5y,
27.45=x+7y
Answer
7
Step-by-step explanation:
If answered correctly and to be the first to answer gets big brain and
Help quick please
Sylvia invested $500 in an account compounded annually with an interest rate of 8%. manuel invested $600 in an account with a compound interest rate of 7.25%. using the rule of 72, startfraction 72 over t endfraction, who will double their money first?
a. sylvia will double her money first, in approximately 9 years.
b. manuel will double his money first, in approximately 10 years.
c. manuel will double his money first, in approximately 9 years.
d. sylvia will double her money first, in approximately 10 years.
Using the rule of 72, startfraction 72 over t endfraction, Manuel will double his money first, in approximately 9 years. Option C is the answer.
The rule of 72The rule of 72 is a quick and simple way to estimate the number of years it takes for an investment to double given the
interest rate. It is calculated by dividing 72 by the interest rate.
For example, if an investment has an interest rate of 8%, it will take approximately 72 / 8 = 9 years to double the investment.
Applying this rule, we can estimate the time it will take for Sylvia's investment to double: 72 / 8 = 9 years.
And for Manuel's investment to double: 72 / 7.25 = 10 years.
Since Manuel's investment will double in approximately 9 years, he will double his money first.
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A student designed a flag for the school's Gaming Club. The design is rectangular with vertices at (3, 7), (11, −9), and (3, −9). Find the missing vertex and the area of the flag in square inches?
The missing vertex is (−9, 7) with an area of 16 in2.
The missing vertex is (7, 11) with an area of 16 in2.
The missing vertex is (−9, 11) with an area of 128 in2.
The missing vertex is (11, 7) with an area of 128 in2.
The missing vertex is (11, 7) with an area of 128 in2.
A coach needs to choose two players from the
hockey team to be captain and assistant
captain. If there are 20 players on the team,
how many ways he can assign the two roles?
A. 100
B. 190
C. 380
D. 450
Answer:
380
Step-by-step explanation:
help me pleaseeeeeeee
Answer:
x=11°
Step-by-step explanation:
opposite angles are equal
so 10x-7 is the same as 103
this looks like
10x-7=103
now you solve it
10x=110
x=11
a menorah holds one candle for each night of hanukkah and and extra candle called the shamash that is used to light the other candles. how many candles does a hanukkah menorah hold?
The primary eight candles or oil lamps must be on a plane that is higher or lower than the shamash.
A nine-branched candelabrum known as a Hanukkah menorah, also known as a hanukkiah, is lighted during the eight-day Jewish festival of Hanukkah. Eight of the nine branches are held up by lights (candles or oil lamps), which stand throughout the eight nights of the festival. One additional light is lighted each night until all eight branches are illuminated on the last night. The candle on the ninth branch, known as the shamash (Arabic for "helper" or "servant"), is used to light the other eight branches.
The seven-branched menorah used in the first Temple in Jerusalem is commemorated by the Hanukkah menorah, which is separate from it. It's one of the most commonly manufactured pieces of Jewish ritual art, along with the Star of David and the menorah with seven branches.
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12
B is the midpoint of AC, D is the midpoint of CE,
and AE = 13. Find BD. The diagram is not to
scale.
A
B
C
D
E
A.
B.
CD
D.
(14) m
mz
fror
Answer:
J. 6.5
Step-by-step explanation:
Theorem:
In a triangle, a segment that has as endpoints the midpoints of two sides is parallel and half the length of the third side.
Here, BD is half the length of AE.
BD = AE/2 = 13/2 = 6.5
Write an inequality, in slope-intercept form, for the graph below. If necessary,use "<=" for < or ">" for >.(-3,0)(0, -3)
Let:
\(\begin{gathered} (x1,y1)=(-3,0) \\ (x2,y2)=(0,-3) \end{gathered}\)The slope m is given by:
\(m=\frac{y2-y1}{x2-x1}=\frac{-3-0}{0-(-3)}=\frac{-3}{3}=-1\)Using the point-slope equation:
\(\begin{gathered} y-y1=m(x-x1) \\ y-0=-1(x-(-3)) \\ y=-x-3 \end{gathered}\)since the area is above the line, and the line is continuous:
\(y\ge-x-3\)You are given n = 8 measurements: 4, 4, 7, 6, 4, 6, 6, 8. (a) Calculate the range. 4 (b) Calculate the sample mean, x. x=5625 (c) Calculate the sample variance, s2, and standard deviation
(a)The range of the given set of measurements is 4.
(b)The sample mean of the given set of measurements is approximately 5.625.
(c)The sample variance of the given set of measurements is approximately 2.337768, and the sample standard deviation is approximately 1.529.
(a) The range is the difference between the largest and smallest values in the set of measurements. In this case, the largest value is 8 and the smallest value is 4, so the range is 8 - 4 = 4.
To calculate the range, we subtract the smallest value from the largest value. In this case, the largest value is 8 and the smallest value is 4.
Range = Largest value - Smallest value
Range = 8 - 4
Range = 4
The range provides a simple measure of the spread or dispersion of the data. In this case, the range tells us that the values range from the smallest value of 4 to the largest value of 8, with a difference of 4 between them.
(b) The sample mean, denoted as x, is the sum of all the measurements divided by the total number of measurements.
To calculate the sample mean, we add up all the measurements and then divide by the total number of measurements. In this case, we have 8 measurements.
Sum of measurements = 4 + 4 + 7 + 6 + 4 + 6 + 6 + 8 = 45
Sample mean = Sum of measurements / Total number of measurements
Sample mean = 45 / 8
Sample mean ≈ 5.625
The sample mean represents the average value of the measurements and provides a measure of central tendency.
(c) The sample variance, denoted as s^2, measures the variability or dispersion of the data points around the sample mean. It is calculated as the average of the squared differences between each measurement and the sample mean.
To calculate the sample variance, we first calculate the squared difference between each measurement and the sample mean. Then, we average those squared differences.
Squared difference for each measurement:
(4 - 5.625)^2 = 2.890625
(4 - 5.625)^2 = 2.890625
(7 - 5.625)^2 = 1.890625
(6 - 5.625)^2 = 0.140625
(4 - 5.625)^2 = 2.890625
(6 - 5.625)^2 = 0.140625
(6 - 5.625)^2 = 0.140625
(8 - 5.625)^2 = 5.390625
Sum of squared differences = 2.890625 + 2.890625 + 1.890625 + 0.140625 + 2.890625 + 0.140625 + 0.140625 + 5.390625 = 16.364375
Sample variance = Sum of squared differences / (Total number of measurements - 1)
Sample variance = 16.364375 / (8 - 1)
Sample variance ≈ 2.337768
The standard deviation, denoted as s, is the square root of the sample variance.
Sample standard deviation = √(Sample variance)
Sample standard deviation = √(2.337768)
Sample standard deviation ≈ 1.529
These measures provide information about the dispersion or spread of the data points around the sample mean. A higher variance or standard deviation indicates greater variability in the measurements.
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What is the solution to the inequality below?
12+x2 3(x-6)
A. X
X5 9
O B. Xs12
O c. xs5
O D. xs 15
What’s the answer
Answer:
x ≤ 15
Hope you could get an idea from here.
Doubt clarification - use comment section.
plz help me with this question.....
Answer:
See Below.
Step-by-step explanation:
The sum of an A.P. is given by:
\(\displaystyle S_n=\frac{n}{2}(a+x_n)\)
Where n is the number of terms, a is the initial term, and xₙ is the last term.
Therefore:
\(\displaystyle S_{30}=\frac{30}{2}\Big(a+x_{30}\Big)=15(a+x_{30})\)
And likewise:
\(\displaystyle S_{20}=\frac{20}{2}\Big(a+x_{20}\Big)=10(a+x_{20})\\\\ S_{10}=\frac{10}{2}\Big(a+x_{10}\Big)=5(a+x_{10})\)
Substitute:
\(15(a + x_{30}) = 3(10 (a + x_{20}) - 5(a + x_{10} ))\)
Distribute:
\(15a+15x_{30}=30a+30x_{20}-15a-15x_{10}\)
Simplify:
\(15x_{30}=30x_{20}-15x_{10}\)
Simplify:
\(x_{30}=2x_{20}-x_{10}\)
The nth term for an A.P. is:
\(x_n=a+d(n-1)\)
Where a is the initial term and d is the common difference.
So, it follows that:
\(x_{30}=a+d(30-1)=29d+a\\ x_{20}=a+d(20-1)=19d+a\\ x_{10}=a+d(10-1)=9d+a\)
Therefore:
\(29d+a=2(19d+a)-9d-a\)
Which follows that:
\(29d+a=38d+2a-9d-a\\ \\ 29d=29d \\\\ d\stackrel{\checkmark}{=}d\)
QED.