Question 1042056
.
Use the quadratic formula to solve the equation. If necessary, round to the nearest hundredth.
 A rocket is launched from atop a 76-foot cliff with an initial velocity of 135 ft/s.
 a. Substitute the values into the vertical motion formula h=-16t2+vt+c Let h = 0. 
b. Use the quadratic formula find out how long the rocket will take to hit the ground after it is launched. Round to the nearest tenth of a second.
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<pre>
The equation after substitution is

{{{h}}} = {{{-16t^2 + 135t + 76}}}

( 135 goes as "v", 76 goes as "c" ).  It is your answer to question a).

To answer question b), solve this quadratic equation

{{{-16t^2 + 135t + 76}}} = {{{0}}}

and take the positive root.
</pre>

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