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4 years ago

Solve, using the substitution method.

1 answer:

6 0

5x+2y=7
y=x-7

5x=7-2y
5x=7-2(x-7)
5x=7-2x+14
5x+2x=7+14
7x/7=21/7
x=3

y=x-7
y=3-7
y=-4

Answer is B

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2x - 4x-7x-2x =10-7+3-1

Sophie [7]

Answer:

x = -5/11

Step-by-step explanation:

2x - 4x-7x-2x =10-7+3-1

Combine like terms

-11x = 5

Divide each side by -11

-11x/-11 = 5/-11

x = -5/11

6 0

3 years ago

Read 2 more answers

PLEASE I WILL GIVE BRAINLIEST IF ONLY UR CORRECT.

patriot [66]

Answer:

Mary removed the dollar sign from (X.)

We know this because $4.00x$5.00=$20.00 so that’s correct and we know that $12.50x $4.00=$50.00. So, our only error here is that there is no dollar sign in our (X) numbers. So that is Mary’s mistake. We can correct it by simply adding a dollar sign to 20 to make $20.00 and adding another dollar sign to 50 to make $50.00

Step-by-step explanation:

hope this helps

3 0

3 years ago

Calculate the perimeter if the value of x is 5.

IceJOKER [234]

Ah u again lol

Perimeter of Isosceles Triangle = 2x + 8
= 2(5) + 8
= 10 + 8
= 18

Therefore, the perimeter is 18. Maybe lol

5 0

3 years ago

Read 2 more answers

Finding an Equation of a Tangent Line In Exercise, use implicit differentiation to find an equation of the tangent line to the g

Karo-lina-s [1.5K]

Answer:

$y=\frac{4}{3}-\frac{x}{3e}$

Step-by-step explanation:

Equation of tangent line of given function at (e,1) is found by implicitly differentiating the given function w.r.to x

$y^{2}+ln(xy)=2\\\\y^{2}+ln(x)+ln(y)=2\\\\\frac{d}{dx}(y^{2}+ln(x)+ln(y))=\frac{d}{dx}(2)\\\\2y\frac{dy}{dx}+\frac{1}{x}+\frac{1}{y}\frac{dy}{dx}=0\\\\\frac{dy}{dx}(2y+\frac{1}{y})=-\frac{1}{x}\\\\\frac{dy}{dx}=-\frac{y}{x(2y^{2}+1)}\\\\at (e,1)\\\\\frac{dy}{dx}=-\frac{1}{e(2+1)}\\\\\frac{dy}{dx}=\frac{1}{3e}$

Equation of tangent line is

y-y₁=m(x-x₁)

at (e,1)

$y-1=-\frac{1}{3e}(x-e)\\\\y=1-\frac{1}{3e}(x-e)\\\\y=1+\frac{1}{3}-\frac{x}{3e}\\\\y=\frac{4}{3}-\frac{x}{3e}\\$

6 0

4 years ago

Suppose that at Northside High, the number of hours per week that seniors spend on homework is approximately Normally distribute

Aliun [14]

Answer:

The mean of the sampling distribution of means for the 36 students is of 18.6 homework hours per week.

Step-by-step explanation:

Central Limit Theorem

The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean $\mu$ and standard deviation $\sigma$ , the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean $\mu$ and standard deviation $s = \frac{\sigma}{\sqrt{n}}$ .

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

In this question:

For the population, the mean is 18.6. So, by the Central Limit Theorem, the mean of the sampling distribution is also 18.6.

3 0

3 years ago