SOLUTION: CAN SOMEONE PLEASE HELP ME WITH THIS PROBLEM: A ball is thrown downward from a window in a tall building. Its position at time t in seconds is s = 16t^2 + 32t, where s is in fee

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Question 161256: CAN SOMEONE PLEASE HELP ME WITH THIS PROBLEM:
A ball is thrown downward from a window in a tall building. Its position at time t in seconds is s = 16t^2 + 32t, where s is in feet. How long (to the nearest tenth) will it take the ball to fall 175 feet?
Answer by nerdybill(7384) (Show Source):
You can put this solution on YOUR website!
The problem gives you the equation:
s = 16t^2 + 32t
.
And, it gives you 's', the distance 175 feet
.
175 = 16t^2 + 32t
0 = 16t^2 + 32t + 175
Since we can't factor, we must apply the quadratic equation.
It will produce two numbers:
t = (2.5, -4.5)
We can toss out the negative answer (since it doesn't make sense)
Solution: 2.5 seconds
.
Below is the quadratic equation solved:

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=12224 is greater than zero. That means that there are two solutions: .

Quadratic expression can be factored:

Again, the answer is: 2.45506874027131, -4.45506874027131. Here's your graph: