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MarkFL

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The length of a rectangle is increasing at a rate of 9 cm/s and its width is increasing at a rate of 5 cm/s...?The length of a rectangle is increasing at a rate of 9 cm/s and its width is increasing at a rate of 5 cm/s. When the length is 14 cm and the width is 12 cm, how fast is the area of the rectangle increasing?

Using a=lw, we have

(dA/dt) = l * (___?___) + (___?___) * (dl/dt)___3.9, 2

I have posted a link there to this topic so the OP can see my work.