Remark Let the cost of each book = x 9*x + 18 = 315 Subtract 18 from each side 9x + 18 - 18 = 315 - 18 9x = 297 Divide both sides by 9 9x/9 = 297 / 9 x = 33
Conclusion Each book cost 33 dollars.
A small point. You really don't have to offer this many points. 15 or even 10 will get someone's attention.
