SOLUTION: solve by substitution: 1: x-y=-8 y=3x 2: 2x+y=1 x=8-3y Solve: 3:x+y=20 -2x+y=5 4:3x+y=8 x-y=12

Algebra ->  Coordinate Systems and Linear Equations  -> Lessons -> SOLUTION: solve by substitution: 1: x-y=-8 y=3x 2: 2x+y=1 x=8-3y Solve: 3:x+y=20 -2x+y=5 4:3x+y=8 x-y=12      Log On