Question 124439
H=-16T^2-32T+320
64=-16T^2-32T+320
-16T^2-32T+320-64=0
-16T^2-32T+256=0
-16(T^2+2T-16)=0
USING THE QUADRATIC EQUATION:{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}} 
X=(-2+-SQRT[2^2-4*1*-16])/2*1
X=(-2+-SQRT[4+64])/2
X=(-2+-SQRT68)/2
X=(-2+-8.246)/2
X=(-2+8.246)/2
X=6.246/2
X=3.123 SECONDS. ANSWER FOR THE TIME FOR THE BALL TO BE @ 64 FT FROM THE GROUND.