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A rectangle has length x falling 2 cm/min and width y rising 3 cm/min. Find the area's rate at x = 8, y = 5.
A−10 cm²/min
B6 cm²/min
C24 cm²/min
D14 cm²/min
Answer & Solution
Correct answer: D. 14 cm²/min
dA/dt = y(dx/dt) + x(dy/dt) = 5(−2) + 8(3) = 14 cm²/min.
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