+128406 A. Two equations - Two Unknowns...we can solve by the elimination method
B. Let x be the price of the hardcover book and y be the price of the paperback...and we have
4x + 10y = 64
5x + 7y = 58
C. Multiply the top equation through by 5 and the bottom equation through by -4 and we get
20x + 50y = 320
-20x - 28y = -232 add these
22y = 88 divide both sides by 22
y = 4 ⇒ cost of paperback in dollars
And using 4x + 10y = 64, the cost of the hardback can be found as
4x + 10(4) = 64
4x + 40 = 64 subtract 40 from both sides
4x = 24 divide both sides by 4
x = 6 ⇒ cost of hardback in dollars
