SOLUTION: Can someone please help me with this problem: A ball is thrown downward from a window in a tall building. Its position at time t in seconds is s = 16t^2 + 32t, where s is in fee

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Can someone please help me with this problem: A ball is thrown downward from a window in a tall building. Its position at time t in seconds is s = 16t^2 + 32t, where s is in fee      Log On


   

Question 161515This question is from textbook finite mathematics
: Can someone please help me with this problem:
A ball is thrown downward from a window in a tall building. Its position at time t in seconds is s = 16t^2 + 32t, where s is in feet. How long (to the nearest tenth) will it take the ball to fall 175 feet? This question is from textbook finite mathematics

Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
s = 16t^2 + 32t
175=16t^2+32t
16t^2+32t-175=0
Using the quadratic equation:t+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+We get:
t=(-32+-sqrt32^2-4*16*-175])/2*16
t=(-32+-sqrt[1,024+11,200])/32
t=(-32+-sqrt12,224)/32
t=(-32+-110.562)/32
t=(-32+110.562)/32
t=78.562/32
t=2.455 seconds
Proof:
175=16*2.455^2+32*2.455
175=16*6.027+78.56
175=96.432+78.56
175~174.992