Question

Find the solution to the equations.

3x - y = -4
x + y = 0

Answer 1

you can use elimination with these equations so you add both
3x-y=-4
+x +y=0
4x=-4 divide by 4
x=-1 then substitute x into either equation i will show the 2nd
-1+y=0
y=1

Answer 2

Easy peasy!

We have,

3x - y = -4
x + y = 0

Solve the second equation for y,

x + y = 0
y = -x

Plug that in the first equation,

3x - (-x) = -4
3x+x=-4
4x=-4
x=-1

Then you can plug that into the other equation,

x + y = 0
(-1) + y = 0
y = 1