Answer: The closest time is 0.954 seconds
Step-by-step explanation:
The height of the Frisbee from the ground is given by
s(t) = -16t^2 +12t + 15
t is the time in seconds. If we input a value for t, we would get the distance of the Frisbee above the ground in feets at that given time.
We want to determine the time at which the Frisbee would be 10 feets above the ground. The equation becomes
10 = -16t^2 +12t + 15
-16t^2 +12t + 15 - 10 = 0
-16t^2 +12t + 5 = 0
We will solve for x using the general formula for quadratic equations
x = [-b+-√b^2 - 4ac]/2a
a = -16
b = 12
c = 5
x = [-12+-√12^2 -( 4 × -16 × 5)]/2 × 5
x = [-12+-√144 + 320]/10
x = [-12+-√464]/10
x =[ -12+21.54]/10 or x =[ -12- 21.54]/10
x = 9.54/10 or x = -33.54/10
x = 0.954 or x = -3.354
Since t is greater than or equal to 0 as stated, the time will be
0.954 seconds
