Question

Need help with this 3x-5y=-8
y=x

Answer 1

you have a system of equation where:
Y = X

We can use this to find either x or y on the first equation, which ever you find better:

3x - 5y = -8 (where y = x so,)
3y - 5y = -8
-2y = -8
y = (8/2)
y = 4

if y = 4 and x = 4 we know that:

y = 4
x = 4