Question 1171209
Set up as -16x^2+83x+4=0. there are two solutions, the larger of which is the time the ball hit the ground after being hit. The other is negative and may be ignored.
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rewrite as 16x^2-83x-4=0
x=(1/32)(83 +/- sqrt (83^2+256)); sqrt (7145)=84.53
x=(1/32)(167.53)=5.235 seconds
x at vertex is -b/2a=-83/-32=2.59375 sec.
height was 111.64 feet

{{{graph(300,300,-2,6,-25,120,-16x^2+83x+4,112)}}} (graph shows 112 foot line)