Solving A Word Problem Using A Quadratic Equation With Irrational Roots 3

A ball is thrown from an initial height of 

2

 meters with an initial upward velocity of 

15/ms

. The ball’s height 

h

 (in meters) after 

t

 seconds is given by the following.

h=2+15t-5t^2

Find all values of 

t

 for which the ball’s height is 

7

 meters.

Round your answer(s) to the nearest hundredth