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A queen sized mattress is 20 inches longer than it is wide. A king-sized mattress is 16 inches wider
than the queen sized mattress but has the same length. The area of the king-sized mattress is 1280 square inches
more than that of the queen-sized mattress.
Part A: Write an equation that can be used to determine the area of the king-sized mattress. Define all variables used.
Part B: Determine the dimensions of the king-sized and queen-sized mattress. Show your work!
Thanks in advance,
Emily
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Let x = width of the queen sized mattress.
Then the queen sized mattress is x*(x+20) inches square.
The king sized mattress is (x+16)*(x+20) inches square.
Your equation is
(x+16)*(x+20) - x*(x+20) = 1280.
Simplify it, taking out (x+20) factor first:
(x+20)*(x + 16 - x) = 1280,
16*(x+20) = 1280,
x + 20 = = 80,
x = 80-20 = 60.