Question

can someone please help me with this problem
-4x+y=-4
-2x+4y=-16
solve each system by elimination
thanks anybody

Answer 1

-4x+y=-4
-2x+4y=-16



-4x+y=-4
-2(-2x+4y)=-2(-16)


-4x+y=-4
4x-8y=32


-7y = 28
y = 28/(-7)
y = -4

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-4x+y=-4
-4x-4=-4
-4x=-4+4
-4x=0
x=0/(-4)
x=0


So the solutions are x = 0 and y = -4

Answer 2

how did we get here: -2(-2x+4y)=-2(-16)

Answer 3

I multiplied both sides by -2 because I wanted the coefficient of the x terms to add up to 0 and cancel out


So in equation 1, I have -4x


In equation 2, I have -2x, but I want 4x. So I must multiply that (and everything else in equation 2) by -2 to get that -2x to +4x

Answer 4

from there, I added the two equations, the x terms then cancel out: -4x+4x = 0x = 0, which goes away