Answer:
Step-by-step explanation:
If a ball thrown downward from a window in a tall building is modeled by the equation, s = 16t² + 32t where s in feet, in order to know the time it will take to fall a distance of 276, we will substitute s = 276feet into the equation and calculate for the value of t as shown;
276 = 16t² + 32t
16t² + 32t = 276
Dividing through by 4
4t² + 8t = 69
4t² + 8t - 69 = 0
Using the general formula to find t
t = -b±√b²-4ac/2a
a = 4, b = 8 and c = -69
t = -8±√8²-4(4)(-69)/2(4)
t = -8±√64+1104/8
t = -8±√1168/8
t = -8±34.176/8
t = -8+34.176/8 or -8-34.176/8
t = 3.272 or -5.272
neglecting the negative time, t = 3secs to the nearest seconds
It will take the all 3secs to fall 276 feets
