Question

Solve the system by the elimination method.
2x + y - 4 = 0
2x - y - 4 = 0
When you eliminate y, what is the resulting equation?


x = 0
4x = -8
4x = 8

Answer 1

What do you get when you add up the equations

2x + y - 4 = 0
2x - y - 4 = 0

Answer 2

can you explain?

Answer 3

http://openstudy.com/updates/52966a25e4b0867562033362

Answer 4

notice how +y added to -y gives you

y + (-y) = y - y = 0y = 0

Answer 5

so that means when you add the equations up, the y terms will cancel out

Answer 6

so what happens when you add up the x terms?

Answer 7

I assuming you are wanting to understand it, rather than the "exercise asks you to explain it"

Answer 8

because it was rather clear in the previous posting