SOLUTION: A rock is thrown from the top of a tall building. The distance D, in feet, between the rock and the ground T seconds after it is thrown is given by {{{d=-16t^2-4t+350}}}. How long

Algebra ->  Test -> SOLUTION: A rock is thrown from the top of a tall building. The distance D, in feet, between the rock and the ground T seconds after it is thrown is given by {{{d=-16t^2-4t+350}}}. How long       Log On


   

Question 34302: A rock is thrown from the top of a tall building. The distance D, in feet, between the rock and the ground T seconds after it is thrown is given by d=-16t%5E2-4t%2B350. How long after the rock is thrown is it 320 feet from the ground?
Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
320=-16T~2-4T=350 OR 16T~2+4T-30=0 OR (4T-5)(4T+6)=0 OR T=5/4 SEC OR 1.25 SEC