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3 years ago

1) y=7x- 12-3x+4y=2

Mathematics

1 answer:

ioda3 years ago

8 0

Answer:

x = 2

y = 2

Step-by-step explanation:

Given that:

y=7x- 12 -------- eq1

-3x+4y=2 ------ eq2

eq1 can be written as:

7x - y = 12

Multiplying this equation by 4 we get:

28x - 4y = 48 --------- eq3

Adding eq2 and eq3 we get:

28x - 3x = 48+ 2

25x = 50

x = 2

Now put this equation in eq1

y = 7(2) - 12

y = 14 - 12

y = 2

i hope it will help you!

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Answer:

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Step-by-step explanation:

Assuming that the floor of the room is rectangular, then its area is equal to the product of its length times its width.

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Let's now call A 'the area that was covered with tiles.

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3 years ago

On a standardized exam, the scores are normally distributed with a mean of 165 and astandard deviation of 40. Find the z-score o

vladimir1956 [14]

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$\begin{gathered} z-score=\frac{(x-\mu)}{\sigma}_{} \\ \mu=\operatorname{mean} \\ \sigma=s\tan dard\text{ deviation} \\ x=\text{score} \end{gathered}$

Step 2: Substitute the given parameters in the formula

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1 year ago

A random sample of n = 45 observations from a quantitative population produced a mean x = 2.5 and a standard deviation s = 0.26.

oee [108]

Answer:

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The null hypothesis is rejected.

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Step-by-step explanation:

This is a hypothesis test for the population mean.

The claim is that the population mean μ exceeds 2.4.

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As the P-value (0.0066) is smaller than the significance level (0.05), the effect is significant.

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3 years ago

Read 2 more answers

What is the answer and work to 15% of 375

vladimir2022 [97]

$15percent = .15
\\.15*375= 15percentof 375
\\\boxed{56.25}$

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3 years ago

1) y=7x- 12-3x+4y=2​

1) y=7x- 12-3x+4y=2