# algebra

posted by .

Solve the system by addition or substitution.
16x-4y=20
y=4x-4
I ask for help with this and forgot to add the problem. can anyone help me understand how to do this?

16x-4y=20
-4x+y=-4
___________

16x-4y=20
(4)(-4x+y=-4)
______________

16x-4y=20
-16x+4y=-16
______________

0=4

16x - 4(4x-4) = 20
16x - 16x - 16 = 20
-16 = 20

It doesn't work. Anonymous is right. Empty Set.

• algebra -

76-78

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