Latest book Aptitude Question SOLUTION: Solve using the substitution method. #1 y=5-x 3x-4y=-20 #2 x+2y=6 2x+3y=8 #3 3x+y=1 x=2y+5 #4 x+y=6 y=3-2x #5 s+t=5 s=13-3t #6 x-y=4 y=2-x