What is the solution to the following system of equations? 3x-4y=-35 3x+4y=5

3x-4y = -35 (1)
3x+4y = 5 (2)
Add equation (1) and (2)
6 x = -30
x = -30/6 = -5
Substitute at equation (2)
3 * -5 + 4y =5
4y = 5+15 = 20
y = 20/4 = 5

The solution of the system:
x = -5 and y = 5