Answer:
Ball hits the ground after 4.5 sec
Step-by-step explanation:
Let a -1, so that the leading coefficient is positive
So our quadratic is
The key coefficients of two binomial variables can be 1 and 16, or 2 and 8, or 4 and 4, for the leading coefficient of 16.
Yet they can't actually be 4 and 4 because the linear (x) term coefficient has to be a multiple of 4, which it isn't and leading coefficients 1 and 16 on the binomial factors is not likely.
So, 2 and 8 taken as the leading coefficients of two binomial factors.
For constant 405, possible factorizations are
Taking first factor, thus we find negative value for given time t. But second time equivalent to zero gives the value of 4.5 for t
Thus ball hits the ground after 4.5 sec
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