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  1. #1
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    Question related rates

    A triangle is increasing in size. The base is increasing at a rate of 5 ft/s while the height is increasing at a rate of 2 ft/s. At what rate is the area increasing at the instant the base of the triangle is 10 ft and the height is 6 ft?

    hurts my brain
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  2. #2
    Grand Panjandrum
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    Quote Originally Posted by xSMUxCHEERLEADINGx View Post
    A triangle is increasing in size. The base is increasing at a rate of 5 ft/s while the height is increasing at a rate of 2 ft/s. At what rate is the area increasing at the instant the base of the triangle is 10 ft and the height is 6 ft?

    hurts my brain
    Area of triangle is:

    A(t)=\frac{b(t)h(t)}{2}

    where b(t) and h(t) are the base and height at time t.

    So (using the product rule):

    A'(t)=\frac{b(t)h'(t)+b'(t)h(t)}{2}

    Now you want to find A'(t) when b'(t)=5 ft/s , h'(t)=2 ft/s, b(t)=10 ft, h(t)=6 ft

    CB
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  3. #3
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    I got 25 ft per second
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