10x-5y=20 solve for x

Answer:

D

Step-by-step explanation:

Given the 2 equations

a + b = 2 → (1)

a - b = - 4 → (2)

Add the equations term by term to eliminate b

2a + 0 = - 2

2a = - 2 ( divide both sides by 2 )

a = - 1

Substitute a = - 1 into (1) and solve for b

- 1 + b = 2 ( add 1 to both sides )

b = 3

Then

ab = - 1 × 3 = - 3 → D

Answer:

option d

Step-by-step explanation:

a+b=2. ,. a-b = -4

a= 2-b

substituting values, we get

(2-b) - b = -4

2 -b -b =-4

2 -2b =-4

-2b = -4-2

2b= 6

b =3

a = 2-3

a= -1

ab = 3×-1

ab = -3

Answer:

A is the solution!

Step-by-step explanation:

-1.6

In statistics, a hypothesis is an assumption about a population parameter. A research question is a question that a research study intends to answer. In research studies, hypotheses and research questions are used to guide the research process and help researchers to focus their attention on specific topics.

The following are examples of potential hypotheses or research questions to relate variables in each of the following examples.
Example 1:
Variables: Gender and job satisfaction
Research Question: Does gender have an impact on job satisfaction?
Hypothesis: Job satisfaction is not dependent on gender.

Example 2:
Variables: Education and income
Research Question: Is there a relationship between education and income?
Hypothesis: There is a positive relationship between education and income.

Example 3:
Variables: Exercise and mental health
Research Question: Does exercise have a positive effect on mental health?
Hypothesis: Exercise is associated with improved mental health.

Example 4:
Variables: Age and technology use
Research Question: Is there a relationship between age and technology use?
Hypothesis: Younger people use technology more than older people.

Example 5:
Variables: Stress and sleep
Research Question: Does stress affect sleep quality?
Hypothesis: Higher levels of stress lead to poorer sleep quality.
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The value of Three less than eight times a number is at least 15 is x≥6

Equations come in two varieties: identities and conditional equations. All possible values of the variables result in an identity. Only certain combinations of the variables' values make a conditional equation true. Two expressions joined by the equals symbol ("=") form an equation.

A mathematical equation is a statement that two amounts or values are equal, such as 6 x 4 = 12 x 2. 2. A noun that counts. When two or more components must be taken into account collectively in order to comprehend or explain the overall situation, this is known as an equation.

Given ,

8x

3 less goes to 8x-3

then there is at least 15 which changes to

8x-3≥15

Then solve for x:

add 3 to the sides--> 3x≥15+3

3x≥18

Divide both of the sides by 3

x≥6

Therefore  the value of three less than eight times a number is at least 15 is x≥6

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Ok, I'll try, the picture is below.

The ordered pair (x, y) that is a solution to the equation -x + 5y = 9 is (1, 2).

To find the ordered pair (x, y) that is a solution to the equation -x + 5y = 9, we need to solve the equation for x and y simultaneously. Here's how we can do it:

-x + 5y = 9

Let's solve this equation for x:

x = 5y - 9

Now, we can choose any value for y and substitute it into the equation to find the corresponding value of x. Let's arbitrarily choose y = 2:

x = 5(2) - 9

x = 10 - 9

x = 1

Therefore, the ordered pair (x, y) that is a solution to the equation -x + 5y = 9 is (1, 2).

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The statement is true that 95% of all possible sample means will fall above 76.71.

We know that the sample mean can be calculated using the formula;

\($\bar{X}=\frac{\sum X}{n}$\).

Given that the mean is 80 and the variance is 400 for the population and the sample size is 100. The standard deviation of the population is given by the formula;

σ = √400

= 20.

The standard error of the mean can be calculated using the formula;

SE = σ/√n

= 20/10

= 2

Substituting the values in the formula to get the sampling distribution of the mean;

\($Z=\frac{\bar{X}-\mu}{SE}$\)

where \($\bar{X}$\) is the sample mean, μ is the population mean, and SE is the standard error of the mean.

The sampling distribution of the mean will have the mean equal to the population mean and standard deviation equal to the standard error of the mean.

Therefore,

\(Z=\frac{76.71-80}{2}\\=-1.645$.\)

The probability of the Z-value being less than -1.645 is 0.05. Since the Z-value is less than 0.05, we can conclude that 95% of all possible sample means will fall above 76.71.

Conclusion: Therefore, the statement is true that 95% of all possible sample means will fall above 76.71.

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The magnitude of Fowler's operating leverage can be calculated using the formula: Operating Leverage = % Change in Operating Income / % Change in Sales

To find the magnitude, we need to compare the percentage change in operating income to the percentage change in sales.

However, the information provided does not include any percentage changes, so we cannot calculate the exact magnitude.

The given options are: 1.35, 1.29, 1.15, and 2.88. Since we cannot calculate the exact magnitude, we can only choose the closest option based on the available information.

Without any additional context or data, it is not possible to determine the correct answer. However, based on the given options, the nearest choice to 1.35 would be the correct answer.

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Answer:

Lucky you Divide each side by 3

Step-by-step explanation:

Give me those points now jk jk

It will take approximately 11.552 years for $1,900.00 to double if it is invested at 6% compounded monthly.

To find the amount of time it takes for an investment to double, we use the compound interest formula: A = P(1 + r/n)^(nt), where A is the amount after t years, P is the principal amount, r is the annual interest rate, n is the number of times interest is compounded per year, and t is the time in years.

In this case, we know that P = $1,900.00, r = 6%, and n = 12 (since interest is compounded monthly). We want to solve for t when A = 2P = $3,800.00. Substituting these values into the formula, we get:

$3,800.00 = $1,900.00(1 + 0.06/12)^(12t)

Simplifying and solving for t, we get:

ln(2) = 12t ln(1 + 0.06/12)

t = ln(2)/(12 ln(1 + 0.06/12)) ≈ 11.552

Therefore, it will take approximately 11.552 years for $1,900.00 to double if it is invested at 6% compounded monthly. It is important to understand the effects of compounding on investments to make informed financial decisions.

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The table represents a linear relationship.

To determine if the table represents a linear relationship, we can check if there is a constant rate of change between the x-values and y-values.

Let's calculate the rate of change between each pair of points:

Rate of change between (-2, -1) and (0, 0):

Change in y = 0 - (-1) = 1

Change in x = 0 - (-2) = 2

Rate of change = Change in y / Change in x = 1 / 2 = 0.5

Rate of change between (0, 0) and (2, 1):

Change in y = 1 - 0 = 1

Change in x = 2 - 0 = 2

Rate of change = Change in y / Change in x = 1 / 2 = 0.5

Rate of change between (2, 1) and (4, 2):

Change in y = 2 - 1 = 1

Change in x = 4 - 2 = 2

Rate of change = Change in y / Change in x = 1 / 2 = 0.5

The rate of change between each pair of points is constant and equal to 0.5. This indicates that there is a constant rate of change, which confirms that the relationship between x and y in the table is linear.

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Answer: ---

Step-by-step explanation:

Divide the hight of the stack by 8, multiply that by 12, you should have your answer

Answer:

995 pounds took the test got it right

Step-by-step explanation:

Answer:

5 pounds

Step-by-step explanation:

% (percent) means 100

0.5% of (1000 pounds)

= 0.5% × (1000 pounds)

= 0.5 ÷ 100 (1000 pounds)

=  5 pounds

Answer:-370

Step-by-step explanation:

Answer: 35

Step-by-step explanation: 36−(−4)+5−10 =40+5−10

45-10=35 :) hope this helps!

y = (-1/2)x - 7/2 is the equation of the given point and slope.

To graph the point (3, -5) and a line with a slope of -1/2, we can use the point-slope form of a linear equation.

The point-slope form of a linear equation is given by:

y - y1 = m(x - x1)

where (x1, y1) represents a point on the line, and m represents the slope.

Plugging in the values, we have:

y - (-5) = (-1/2)(x - 3)

Simplifying:

y + 5 = (-1/2)x + 3/2

Subtracting 5 from both sides:

y = (-1/2)x + 3/2 - 5

y = (-1/2)x - 7/2

Now we have the equation y = (-1/2)x - 7/2, which represents a line with a slope of -1/2 passing through the point (3, -5).

To graph the line, plot the point (3, -5) on the coordinate plane and then use the slope to find additional points. For every 2 units you move to the right, move 1 unit down to find other points. Connect the plotted points to draw the line.

The resulting graph will show the point (3, -5) and a line with a slope of -1/2.

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Answer:

u = -1/5

Step-by-step explanation:

name me brainliest please.

Answer:

Height of the building = 77 ft.

Step-by-step explanation:

Let the height of the building (AB) = h feet

It's given that height of a woman (ED) = 5 feet 3 inches

                                                              ≈ 5 feet + \(\frac{3}{12}\) ft

                                                              ≈ 5.25 ft

Length of the shadow (BC) of the building = 55 ft

Length of the shadow (DC) of the woman = 45 in ≈ 3.75 ft

Since, both the triangles ABC and EDC are similar, their corresponding sides will be proportional.

By the property of similar triangles,

\(\frac{AB}{ED}= \frac{BC}{DC}\)

\(\frac{h}{5.25}=\frac{55}{3.75}\)

h = \(\frac{55\times 5.25}{3.75}\)

h = 77 ft

Therefore, height of the building will be 77 ft.

Answer:

If the slope of the line is 3, it either decreases or increases by 3 everytime. (3x) If the y-intercept is 0, then when the line intercepts with the graph, it will intercept with (0, 0)

Step-by-step explanation:

Basically, the slope means how much the line increases or decreases. The y-intercept means where the line will intercept or start on the y-axis. If the y-intercept was 5, it would be (0, 5)

Answer:

Step-by-step explanation:

To perform synthetic division on this polynomial, we will first write the polynomial in standard form, with the terms arranged in decreasing order of the exponent:

(6x^4 - 12x^3 + 9x - 12)

Then, we will use the following steps to perform synthetic division:

Write the divisor, (x - 2), at the top of the division, and write the constant term of the polynomial, (-12), below it.

Multiply the divisor by the constant term and write the result below the constant term.

Bring down the next term of the polynomial, (9x), and add it to the result from step 2.

Multiply the divisor by the result from step 3 and write the result below it.

Bring down the next term of the polynomial, (-12x^3), and add it to the result from step 4.

Multiply the divisor by the result from step 5 and write the result below it.

Bring down the final term of the polynomial, (6x^4), and add it to the result from step 6.

The final result will be the quotient, and any remainder will be discarded. The result of the synthetic division is shown below:

(x - 2) | -12 9x -12x^3 6x^4

|-------------------

-12 6x -24x^2 36x^3

The quotient is (-12 + 6x - 24x^2 + 36x^3).

Note that we can check our work by multiplying the divisor, (x - 2), by the quotient, (-12 + 6x - 24x^2 + 36x^3), and verifying that the result is equal to the original polynomial.

Answer:

103.27 degree

Step-by-step explanation:

You need to find the angle of the interior of the triangle first, and then find the exterior. Hope I helped!

There are four 5's in a deck of cards

The probability of being a 5 would be 4/52 which simplifies to 1/13

The probability of not being a 5 would be 1 - 1/13 = 12/13

Answer:

77.5 cm

Step-by-step explanation:

15.5km* 5 cm on map/ 1 actual km= so 77.5 cm

if my answer helps please mark as brainliest.

If there is no difference between any of the two or more groups being compared, H0 indicates the anticipated outcome of a statistical test. This statement is true.

H0, or the null hypothesis, represents the assumption that there is no significant difference between the groups being compared in a statistical test. It is the default hypothesis that is tested against an alternative hypothesis, H1, which states that there is a significant difference between the groups.

The null hypothesis is essential in hypothesis testing as it serves as the basis for determining whether the results of the test are statistically significant or due to chance. The statistical test is designed to reject the null hypothesis if the calculated p-value is less than the pre-determined significance level, indicating that the observed results are unlikely to have occurred by chance alone.

The acceptance or rejection of the null hypothesis has important implications for decision-making in various fields, such as medicine, psychology, and business. Therefore, it is crucial to carefully construct and test the null hypothesis to ensure that the results are accurate and meaningful.

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Answer:

answer is 152

Step-by-step explanation:

i mutiplied $16 and $8 and got 128 the subtracted 128 and 280 and final answer is 152

Molly conjectured that for any number x greater than 0, x^3 is always greater than 3x^3. However, we need to find a counterexample that disproves her conjecture. We can test the given values -5, 0, 2, and 10 to see if any of them satisfy the inequality.

To determine a counterexample, we substitute the values -5, 0, 2, and 10 into the inequality x^3 > 3x and check if the inequality holds true for any of them.

For -5, we have (-5)^3 = -125 and 3(-5) = -15. Since -125 is not greater than -15, -5 is not a counterexample.

For 0, we have 0^3 = 0 and 3(0) = 0. Since 0 is not greater than 0, 0 is not a counterexample.

For 2, we have 2^3 = 8 and 3(2) = 6. Since 8 is greater than 6, 2 is not a counterexample.

For 10, we have 10^3 = 1000 and 3(10) = 30. Since 1000 is greater than 30, 10 is a counterexample.

Therefore, the value 10 is a counterexample to Molly's conjecture, as it satisfies the inequality x^3 > 3x.

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Answer:

5s

Step-by-step explanation:

45-5=40

Answer: The lowest price you can pay for 15kg of apples is $10.77

Step-by-step explanation:

3.59*3= 10.77 = 15kg

2.49*5= 12.45 = 15kg

Step-by-step explanation:

Simplifying 8a = 2xy + b

Reorder the terms: 8a = b + 2xy

Solving 8a = b + 2xy

Solving for variable 'a'. Move all terms containing a to the left, all other terms to the right.

Divide each side by '8'. a = 0.125b + 0.25xy

Simplifying a = 0.125b + 0.25xy

The given pair of lines are parallel lines.

So, graph the lines on the given equation:

(Refer to the graph attached below)

We can easily look at the graph and tell that the given lines of the equations are parallel to each other.

Therefore, the given pair of lines are parallel lines.

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Answer:

43

Step-by-step explanation:

b) The mean is 19.

c) The standard deviation is 0.974.

d) The binomial probability is 20.

A standard deviation (or σ) is a measure of how dispersed the data is in relation to the mean. Low standard deviation means data are clustered around the mean, and high standard deviation indicates data are more spread out.

Given:

n = 20,  p = 0.95,  q = 1 - 0.95 = 0.05

a)  There are only two results per shot and they are independent of each other. Each pitch is independent of the outcome of the other pitches.

b) To calculate the mean of X.

{ E(x) = np }

So, E(x) = 95% of 20

             = 19

c) The Standard Deviation is √npq

= √95/10

= 0.974

d) The binomial probability

p(x = 19) = 20! / 19!(20-19)!

               =20 / 1

                20

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