What is the result of adding these two equations?
6x + 2y = -2
3x – 2y = -5

9x=-7

Step-by-step explanation:

Line up the 2 equations like when you add( one on top of the other)

6x+2y=-2

3x-2y=-5

Your going to add the number from the top and add the number directly below it

That would give you

6x+3x = 9x

2y + (-2y)=0 do not put 0 just leave it blank

they cancel each other out since the number is the same but one is negative and the other is positive

-2 + -5=-7

Finally bring put the answers you got together in the corresponding order according to the equation and bring down the equal sign

Final

9x=-7

step-by-step explanation:

(b) 240

step-by-step explanation:

first, we use the pythagorean formula using the given side lengths to find x. then we use x to find the side lengths. then we add the side lengths to find the perimeter.

pythagorean theorem formula:

a^2 + b^2 = c^2

(x - 20)^2 + (x - 40)^2 = x^2

x^2 - 40x + 400 + x^2 - 80x + 1600 = x^2

x^2 -120x + 2000 = 0

(x - 100)(x - 20) = 0

x - 100 = 0 or x - 20 = 0

x = 100 or x = 20

we see that the solution x = 20 must be discarded because it will give a negative side length and a side length of 0. the only valid solution is x = 100.

perimeter = sum of the lengths of the sides

perimeter = x + x - 20 + x - 40

perimeter = 3x - 60

replace x with 100.

perimeter = 3(100) - 60

perimeter = 300 - 60

perimeter = 240