Question

Daniel kicks a soccer ball up in the air with an initial upward velocity of 64 ft. per second. The ball is 2 ft. above the ground when it is kicked. The following function represents this situation: -16x2 + 64x + 2. How long will it take the ball to reach its maximum height? How high above the ground will it be? (You can use desmos and the quadratic word problem sheet.)

Answer 1

You can also do this by converting to vertex form
-16x^2 + 64x + 2
= -16(x^2  - 4x) + 2
= -16 ((x - 2)^2 - 4) + 2
= -16 (x - 2)^2  + 66

The time to get to maximum height is 2 seconds and maximum height is 66 feet.