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3 years ago

Why is he wrong? What is the correct answer?

Mathematics

1 answer:

Tems11 [23]3 years ago

4 0

Answer:

Step-by-step explanation:

He had the incorrect slope for the second line, his line has a positive slope of one while the equation has a slope of negative 1.

x+y=1

y=-x+1

He graphed x+1 instead of -x+1

If he graphed them correctly the lines would intersect when the equations were equal

2x+4=-x+1

3x+4=1

3x=-3

x=-1, making y=2x+4 become

y=2(-1)+4

y=2

So the solution was supposed to be the point (-1,2)

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Which of the following statements is equivalent to 10x – 30?

Sergeeva-Olga [200]

Answer:

10(x-3)

Step-by-step explanation:

3 0

3 years ago

Given that α and β are the roots of the quadratic equation <img src="https://tex.z-dn.net/?f=2x%5E%7B2%7D%20%2B6x-7%3Dp" id="Tex

siniylev [52]

Answer:

$\large \boxed{\sf \ \ \ p=-11 \ \ \ }$

Step-by-step explanation:

Hello,

$\alpha \text{ and } \beta \text{ are the roots of the following equation}$

$2x^2+6x-7=p$

It means that

$2\alpha^2+6\alpha-7=p \\\\2\beta ^2+6\beta -7=p \\\\$

And we know that

$\alpha= 2\cdot \beta$

So we got two equations

$2(2\beta)^2+6\cdot 2 \cdot \beta -7=p \\\\8\beta^2+12\beta -7=p\\\\ and \ 2\beta ^2+6\beta -7=p \ So \\\\\\8\beta^2+12\beta -7 = 2\beta ^2+6\beta -7\\\\6\beta^2+6\beta =0\\\\\beta(\beta+1)=0\\\\ \beta =0 \ or \ \beta=-1$

For $\beta =0, \ \ \alpha =0, \ \ p = -7$

For $\beta =-1, \ \ \alpha =-2, \ \ p= 2-6-7=-11, \ p=2*4-12-7=-11$

I assume that we are after two different roots so the solution for p is p=-11

b) $\alpha +2 =-2+2=0 \ and \ \beta+2=-1+2=1$

So a quadratic equation with the expected roots is

$x(x-1)=x^2-x$

Hope this helps.

Do not hesitate if you need further explanation.

Thank you

3 0

3 years ago

Question is on the picture !

Nataly [62]

Answer: 122.5

======================================================

Explanation:

First thing to do is to find the perimeter of figure B. Add up all the sides and we get: 5+9+9+12 = 14+21 = 35.

The scale factor 7:2 means that if the perimeter of figure A was 7, then the perimeter of figure B would be 2. Or it could be 14 for A and 4 for B. And so on. The idea is that the two perimeters scale up or down together. This allows us to set up the proportion below in which we can solve for x

(perimeter of A)/(perimeter of B) = 7/2

x/35 = 7/2

x*2 = 35*7 .... cross multiply

2x = 245

2x/2 = 245/2 .... divide both sides by 2

x = 122.5

The perimeter of figure A is 122.5

4 0

3 years ago

15-2x=3x x= please help me

alex41 [277]

15-2x=3x
Add 2x to both sides
15=5x
Divide by 5 on both sides
3=x

Hope it helps (:

7 0

3 years ago

Read 2 more answers

What is the difference between -2 and -6? 8 -8 -4 4

Sedaia [141]

Hi there! The word "difference" means to subtract. -2 - -6=4. Therefore, it would be the last one.

8 0

3 years ago