<PRE><B>Question 1204487</B>
price for a hardcover book is x.
price for a paperback book is x - 2
total spent is 100.
equation is 5 * x + 4 * (x - 2) = 100
simplify to get 5  * x + 4 * x - 8 = 100
combine like terms to get 9 * x - 8 = 100
add 8 to both sides of the equation to get 9 * x = 108
divide both sides of the equation by 9 to get x = 108 / 9
solve for x to get x = 12.
5 * x + 4 * (x - 2) = 100 becomes 5 * 12 + 4 * 10 = 100 which becomes 60 + 40 = 100 which becomes 100 = 100, confirming the value of x is good.
your solution is:
the price of a hardcover book is 12.
the price of a paperback book is 10.
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