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bubbyv13
a foul tip of a baseball is hit straight upward. The function s(t) = -16t^2 +96t+4 describes the ball's height above the ground, s(t), in feet, t seconds after it was hit. Let s'(t)= -32t +96. Use the quadratic formula to determine how many seconds it will take for the ball to hit the ground.
s(t) is the height above the ground. you want to find the t values which make s(t) = 0. s'(t) seems unnecessary for this problem. quadratic formula for \[at^{2} + b{t} + c\] t = \[\frac{ -b \pm \sqrt{b^{2} - 4ac} }{ 2a }\]
it should say: quadratic formula for \[at^{2} + bt +c = 0\] let me know if you have questions about what i said