Question 1153181
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<pre>

For any quadratic function

    f(x) = ax^2 + bx + c

with the negative leading coefficient "a", it gets the maximum at  x = {{{-b/(2a)}}}.



In your case, the quadratic function is  h(t) = -4.9*t^2 + 18t + 8,

so the coefficients are  a = -4.9  and  b = 18.



Thus it gets the maximum at  t = {{{-18/(2*(-4.9))}}} = 1.837 seconds.



<U>ANSWER</U>.  It will take 1.837 seconds to get the maximum height.
</pre>

Solved.


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