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3 years ago

- If 2x2 + 8y = 121.5 and x2 - 8y = 121.5, then x = 9 6.36 16 7

Mathematics

1 answer:

Natalija [7]3 years ago

4 0

Step-by-step explanation:

2x² + 8y = 121.5

x² - 8y = 121.5

Add the equations together to eliminate the y terms.

3x² = 243

x² = 81

x = 9

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What’s the value of x? G 53° 45 H x°

Kazeer [188]

Answer:

x = 98°

Step-by-step explanation:

95 + 53 + (180 - x) = 180

148 + 180 - x = 180

328 - x = 180

328 - x + x = 180 + x

x + 180 = 328

x + 180 - 180 = 328 - 180

x = 98°

7 0

3 years ago

What is the total repayment made, including principal and interest, on a loan of $1,100 at 3.5% interest compounded annually ove

olchik [2.2K]

The total repayment made, including principal and interest is $1262.27

<h3>Compound interest</h3>

The formula for calculating the compound interest is calculated as shown below;

A = P(1+r)^t

where

P is the principal = $1100

rate = 3.5% = 0.035

time "t" =4 years

Substitute

A. = 1100(1+0.035)^4
A = 1100(1.035)^4
A = 1100(1.14752)

A = 1262.27

Hence the total repayment made, including principal and interest is $1262.27

learn more on compound interest here: brainly.com/question/24924853

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8 0

2 years ago

The formula for percentage increase I (given as a decimal) of an investment is I=S−PP, where P is the purchase price and S is th

sattari [20]

18.75/75=(75/75) -
p =(75-18.5)/75
p=56.5/75
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5 0

3 years ago

Read 2 more answers

The vertices of a polygon are P(0,4), Q(5,4), R(5,−3) and S(0,−3). What is

andrezito [222]

Answer:

Perimeter of the polygon p = 24

Step-by-step explanation:

Step(i):-

Given the vertices of a polygon are

P(0,4) ,Q( 5,4) ,R( 5,-3) and S(0,-3)

The distance of PQ

$a = PQ = \sqrt{(4-4)^{2} +(5-0)^{2} } = \sqrt{25} =5$

The distance of QR

$b = Q R= \sqrt{(-3-4)^{2} +(5-5)^{2} } = \sqrt{49} =7$

The distance of RS

$c = RS = \sqrt{(0-5)^{2} +(-3+3)^{2} } = \sqrt{25} =5$

The distance of PS

$d = PS = \sqrt{(0-0)^{2} +(-3-4)^{2} } = \sqrt{49} =7$

Step(ii):-

Perimeter of the polygon

= sum of all sides of polygon

p = a+ b+ c+ d

p = 5+7+5+7

p = 24

Final answer:-

Perimeter of the polygon p = 24

5 0

3 years ago

Cincinnati Paint Company sells quality brands of paints through hardware stores throughout the United States. The company mainta

Gemiola [76]

Answer:

There is no significant interaction between the number of sales calls and the miles driven.

Step-by-step explanation:

The variables are defined as follows:

Dependent (Y) = amount earned in commissions last month

Independent (X₁) = number of miles driven last month

Independent (X₂) = number of sales calls made last month

In this case we need to test whether there is a significant interaction between the number of sales calls and the miles driven.

The hypothesis can be defined as follows:

H₀: There is no significant interaction.

Hₐ: There is a significant interaction.

Assume that the significance level of the test is, α = 0.05.

Use the Data Analysis tool in Excel to form the regression equation.

For the regression equation, we need to compute the values of (X₁ × X₂).

Steps:

Go to Data - Data Analysis - Regression. A dialog box will open.
Select the Y values in the "Input Y range" and values of X₁, X₂ and X₁ × X₂ in the "Input X range".
Click OK.

The output of the regression analysis is attached below.

The regression equation is:

$Y=-455.07+3.128\cdot X_{1}+0.143\cdot X_{2}-0.001\cdot X_{1}X_{2}$

Consider the third table in the regression output.

The test statistic corresponding to the interaction term is:

t = -1.85

The p-value for the test of the interaction term is:

p-value = 0.078.

The p-value of the test is more than the significance value.

The null hypothesis will not be rejected.

Thus, concluding that there is no significant interaction between the number of sales calls and the miles driven.

8 0

4 years ago