8x – 100 + 8x = 12000
8x + 8x = 12000 + 100
16x = 12100
x = 756.25
2*(x-30)+2x=660
2x – 60 + 2x = 660
2x + 2x = 660 + 60
4x = 720
x = 180
8x – 100 + 8x = 12000
8x + 8x = 12000 + 100
16x = 12100
x = 756.25
2*(x-30)+2x=660
2x – 60 + 2x = 660
2x + 2x = 660 + 60
4x = 720
x = 180