Answers:
1) 18x - 6x + 2x = 14x
Combine like terms by subtracting 6 from 18 and adding 2
2) 4b - 7 - 15b + 3 = - 11b - 4
Combine like terms add 4b and - 15b ; add -7 and 3
3) 15(6-g) = 90 - 15g
Distribute the 15 to both terms
4) -24 + 2(y - 9) = 2y - 42
Distribute the 2 to (y-9) and combine like terms
