Solve for each system 4x+6y+5z = 70, 4x+6y = 60, 3x=18

3x=18

3x/3=18/3

x=6

4x+6y = 60

4(6)+6y = 60

24+6y = 60

24+6y-24 = 60-24

6y=36

6y/6=36/6

y=6

4x+6y+5z = 70

4(6)+6(6)+5z = 70

24+36+5z = 70

60+5z = 70

60+5z -60= 70-60

5z=10

5z/5=10/5

z=2