take the second equation and plug it into the first one after you set it equal to x.
so y+4=x then plug it into the first equation.
y=y+4-4
then 4-4=0
so your answer would be y=y which would make it be no solution
3x = x - 4
x = -2
Since y = 3x, then y = 3(-2) = -6. It also satisfies the second equation
how do you solve
y=3x
y=x-4
using substitution
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3x = x-4
2x = -4
x = -2
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y = -6