(-2,-5)
The first goal with equations like these is to get one of the variables to go away. You can do that by adding/subtracting one equation from the other. Then you solve for the one variable. Then you plug that answer into one of the original equations and solve.
1) y=x+2
2) y=1/4x
3) y=-3x+0.5
4) y=0.2x+0.8