Step-by-step explanation:
x + 4 + 3x = 72 Let's agroup all the x
4x + 4 = 72 Subtract 4 on both sides
4x = 68 Divide both sides by 4
x = 17
x + 3 + x – 8 + x = 55 Let's agroup all the x
3x + 3 – 8 = 55 Solve 3 – 8
3x – 5 = 55 Add 5 on both sides
3x = 60 divide both sides by 3
x = 20
