I'll give 99 pointsA ball is thrown into the air with an upward velocity of 80ft/s. Its height H in feet after T seconds id given by the function H= -16T^2+80T+5. What is the maximum height the ball reaches? How long will it take the ball to reach maximum height? How long does it take for the mall to be caught 5 feet off the ground?All I really need help on is the last one.Will some one plz help me.

Accepted Solution

Maximum height is at dH/dt=0H= -16T^2+80T+5dH/dt=-32T+80-32T+80=032T=80T=2.5s when height is maxHmax=-16(2.5)^2+80*2.5)+5=105ftcatching the ball at 5' means solve for T at H=5H= -16T^2+80T+5=5-16T^2+80T=0-16T(T-5)=0so T=0 cannot be the ans or T=5s