Homework Help: Math - solving quadratic equations with factoring

Posted by Amy on Tuesday, January 24, 2012 at 11:13am.

A person jumps off a 20m high cliff into water below. The height of the person above the ground at time t seconds is given by the equation h=-5t^2+30. How long does it take the person to reach the half way mark to the water?

Math - solving quadratic equations with factoring - Steve, Tuesday, January 24, 2012 at 11:15am
10 = -5t^2 + 30

5t^2 = 20
t^2 = 4
t = 2

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