Question

Elimination :
2x+5y=-1
x+3y=0

Answer 1

What happens when you multiple the second equation by -2?

-2x - 6y = 0

Why would I do that?

Answer 2

oh it would be multiplyed by -2!

Answer 3

Now add the two equations.

Answer 4

y=-1???

Answer 5

then plug it in?

Answer 6

No. When you add both equations you get:
2x+5y=-1
-2x-6y=0
-------------
-y=-1
so y=1

Then plug into either of your equations and solve for x.