SOLUTION: If an object is propelled straight upward from ground level with an velocity of 80 feet per second, it's height in feet t seconds later is given by the equation h= - 16t^2 + 80t. A
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-> SOLUTION: If an object is propelled straight upward from ground level with an velocity of 80 feet per second, it's height in feet t seconds later is given by the equation h= - 16t^2 + 80t. A
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Question 615008: If an object is propelled straight upward from ground level with an velocity of 80 feet per second, it's height in feet t seconds later is given by the equation h= - 16t^2 + 80t. After how many seconds is the height 96 feet? Answer by nerdybill(7384) (Show Source):
You can put this solution on YOUR website! If an object is propelled straight upward from ground level with an velocity of 80 feet per second, it's height in feet t seconds later is given by the equation h= - 16t^2 + 80t. After how many seconds is the height 96 feet?
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set h to 96 and solve for t:
h= - 16t^2 + 80t
96= - 16t^2 + 80t
0= - 16t^2 + 80t - 96
0= 16t^2 - 80t + 96
dividing both sides by 16:
0= t^2 - 5t + 6
0=(t+1)(t-6)
t = {-1, 6}
throw out the negative solution (extraneous) leaving
t = 6 seconds
