Question

Solve by the substitution method.

2x + 4y = 8
-5x + y = 13

What is the solution of the ​system?
oobleck
the 2nd equation says that y = 5x+13
So substitute that in the 1st equation, and you have

2x + 4(5x+13) = 8
Solve that for x, and then use that to get y.