SOLUTION: Suppose Charlie O'Brien Of the Braves hits a baseball straight upward at 150 ft/sec from a height of 5ft. Use the formula to determine how long it takes the ball to return to earth

Algebra ->  Complex Numbers Imaginary Numbers Solvers and Lesson -> SOLUTION: Suppose Charlie O'Brien Of the Braves hits a baseball straight upward at 150 ft/sec from a height of 5ft. Use the formula to determine how long it takes the ball to return to earth      Log On


   

Question 348691: Suppose Charlie O'Brien Of the Braves hits a baseball straight upward at 150 ft/sec from a height of 5ft. Use the formula to determine how long it takes the ball to return to earth?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
-32t%5E2+%2B+150t+%2B+5+=+h
h is the height above ground.
At t=0 the height is 5 ft
as it should be.
At t+=+1 sec
-32%2A1%5E2+%2B+150%2A1+%2B+5+=+123 ft ( it's going up)
At t+=+2 sec
-32%2A2%5E2+%2B+150%2A2+%2B+5+=+177 ft (still going up)
At t+=+3 sec
-32%2A3%5E2+%2B+150%2A3+%2B+5+=+167 ft (it's coming down)
It's going to hit ground sometime after 3 sec
Make h+=+0 (ground)
-32t%5E2+%2B+150t+%2B+5+=+0
Solve using quadratic formula
t+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
a+=+-32
b+=+150
c+=+5
t+=+%28-150+%2B-+sqrt%28+150%5E2-4%2A%28-32%29%2A5+%29%29%2F%282%2A%28-32%29%29+
t+=+%28-150+%2B-+sqrt%28+23140+%29%29%2F%28-64%29+
t+=+%28-150+-+152.118%29%2F%28-64%29
You can finish