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Jordan tosses a coin off a bridge into the riverThe height of the cain, f(x) , feet, is represented by the function f(x) = - 16x ^ 2 - 16x + 60 where x represents the time, in secondslong is the coin in the air?

1 Answer

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when the equation has a value of 0 of course the coin lands, so we need to find what x leads to that value.

-16x^2-16x+60=0

We can first divide by 4 on both sides.

-4x^2-4x+15=0

Now multiply -1

4x^2+4x-15=0

(2x-3)(2x+5)=0

x=3/2 or -5/2

But because how many seconds have to be positive, x=-5/2 is an extraneous solution.

The time it have to stay in the air is 3/2 seconds.

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