<PRE><B>Question 194477</B>
h(t) = -16t^2 + v0t + s0 
A potato gun is capable of launching a spud with an initial velocity of 80 feet per second. If the tater takes off from an elevation of 100 feet, how many seconds into its flight will it be at an elevation of 115 feet.
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h(t) = -16t^2 + 80t + 100
At 115 feet:
115 = -16t^2 + 80t + 100
16t^2 - 80t + 15 = 0
t = (10 ą sqrt(85))/4 seconds
One solution for t is on its way up, the other is on its way down.
t = ~ 0.19511 seconds going up
t = ~ 4.80489 seconds going down
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