Posted by carol on .
If a stone is tossed from the top of a 250 meter building, the height of the stone as a function of time is given by h(t) = 9.8t2 – 10t + 250, where t is in seconds, and height is in meters. After how many seconds will the stone hit the ground? Round to the nearest hundredth’s place; include units in your answer.

math 
Henry,
When the stone hits the , the heiht will be zero:
9.8t^2  10t + 250 = 0,
Solve using the Quadratic Formula and
get:
t = 5.59 and 4.57s.
Use positve value:
t = 4.57s.