An arrow is shot vertically upward from the top of a cliff 80 feet tall, with an initial velocity of 64 ft/s, (the acceleration due to gravity is -16ft/sec).

Question

a. Write the quadratic equation representing this scenario when h is 0.
b. Find the roots (solutions) for this quadratic equation, solving by factoring.

Answer 1

assuming the quadratic equation represents the height of the arrow above the ground at the base of the cliff (and that the shot is made just past the edge of the cliff, so the falling arrow does not hit the cliff), then

the height h as a function of time is

h(t) = 80 + 64t - 16t^2

h=0 when the arrow hits the ground at the base of the cliff.

the rest should be no sweat

Answer 2

Thanks Steve