Really having a hard time with this question. any help would be appreciated. Suppose that a cliff diver's height (in feet) after t seconds is given by the model $H = −16t^2+48t+28$ . Find the height after $1.75$ seconds.
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$\begingroup$ Have you tried something? This looks pretty easy. $\endgroup$– Obinna NwakwueMay 25, 2016 at 21:59
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$\begingroup$ Yes, i plugged in a 1.75 for t and it did not work. $\endgroup$– Havili VaitaiMay 25, 2016 at 22:05
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1$\begingroup$ I plugged it in and got 63 without using 7/4. $\endgroup$– user301988May 25, 2016 at 22:18
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1 Answer
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The result is $63$.
$1.75 = 7/4$, so:
$-16(1.75)^2+48\cdot 1.75 + 28 = -16\cdot\frac{49}{16}+48\cdot\frac 74 + 28 = -49 + 12\cdot 7+ 28 = 112-49 = 63.$