SOLUTION: The height of a particular object can be given by the equation h= -16t^2+32t. What is t when h was 12 feet?

Question 917427: The height of a particular object can be given by the equation h= -16t^2+32t. What is t when h was 12 feet?
Answer by srinivas.g(540) (Show Source): You can put this solution on YOUR website!
h = -16t^2+32 t
when h= 12
12 = -16t^2+32 t
subtract 12 on both sides
12-12 =-16t^2+32t-12
0 =-16t^2+32t-12
solve the quadratic equation

Solved by pluggable solver: SOLVE quadratic equation with variable

Quadratic equation (in our case ) has the following solutons:

For these solutions to exist, the discriminant should not be a negative number.

First, we need to compute the discriminant : .

Discriminant d=256 is greater than zero. That means that there are two solutions: .

Quadratic expression can be factored:

Again, the answer is: 0.5, 1.5. Here's your graph:

so t is 0.5 &1.5
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