Question

A golfer hits the golf ball. The quadratic function y = −16x^2 + 80x gives the time x seconds when the golf ball is at height 0 feet. How long does it take for the golf ball to return to the ground? HELP PLEASE!

Answer 1

You need to calculate the two zeros of the function. The first zero is the "start", the second zero is the "end" of the trajectory.

Well...

0 = x(-16x+80)

First zero is x=0 (the start of trajectory)

Second zero:

-16x+80=0.... x=5! (The end of the trajectory!)

Good luck!
M.