3y + 2z = 43 2y + 4z = 50

2y + 4z = 50

2y+4z-4z=50-4z

2y=50-4z

2y/2=50-4z/2

y=25-2z

3y + 2z = 43 sub in y and solve for z

3(25-2z)+2z=43

75-6z+2z=43

75-4z=43

75-75-4z=43-75

-4z=-32

-4z/-4=-32/-4

z=8

y=25-2z

y=25-2(8)

y=25-16

y=9