Answer:
1. x = 3
2. x = 8
3. x = 5
4. x = 8
Step-by-step explanation:
1. 18 = 6x
divide both sides by 6
x = 3
2. x + 7= 15
subtract 7 from both sides
x = 8
3. 2x - 2 = 8
add 2 to both sides
2x = 10
divide 10 by 2
x = 5
4. -1 + x = 7
add 1 to both sides
x = 8