Question 630072:  h(t)= -16t^2+dt+c  
 
 
 
At time t=0, a rocket was launched upward from an initial height of 6 feet. Until the rocket hit the ground, its height, in feet, after t seconds was given by the function h aobve, in which c and d are positive constants. If the rocket reached its maximum height of 350 ft at time t=4, what was the height, in feet, of the rocket at time t=1? 
 
(the answer is 140, by the way) 
please include explanations! 
 Answer by stanbon(75887)      (Show Source): 
You can  put this solution on YOUR website! h(t)= -16t^2+dt+c 
 
At time t=0, a rocket was launched upward from an initial height of 6 feet. Until the rocket hit the ground, its height, in feet, after t seconds was given by the function h aobve, in which c and d are positive constants. If the rocket reached its maximum height of 350 ft at time t=4, what was the height, in feet, of the rocket at time t=1?  
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h(0) = -16*0^2 + d*0 + c = 6 feet 
So, c = 6 
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h(4) = 350 
h(4) = -16*4^2+4d + 6 = 350 
256 + 4d + 6 = 350 
4d = 88 
d = 22 
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Equation:  
h(t) = -16t^2 + 22t + 6 
h(1) = -16 + 22 + 6 
h(1) = 12 feet 
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Cheers, 
Stan H. 
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