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Siska hit a golf ball into the air with an initial velocity of 56 feet per second. The height h in feet of the ball above the ground can be modeled by h=-16t^{2}+56t, where t is the time in seconds after Sisika hit the ball. Find the time it takes the ball to reach 49 feet above the ground.

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MissPhiladelphia
To find the time it takes for the ball to reach the given height, we need an equation that relates the height and time it travel which is given to be h=-16t^{2}+56t. We just substitute the height of 49 feet then solve for t. We do as follows:

h=-16t^{2}+56t
49 = -16t^{2}+56t
t = 1.75 seconds

Hope this answers the question. Have a nice day.
ikuemuyaolusegun

Answer: t=1.75secs

Explanation: The hieght h is related to the time by the given equation

h = -16t² + 56t

Swapping the equation left to right the sign changes

16t² - 56t =-h

But h = 49ft

16t² -56t = -49

Taking -49 to the other side of the equation and equating everything to 0 we have

16t² - 56t + 49 = 0

This is a quadratic equation

Where a=16 , b=-56 and c = 49

t = {- b +or- √{b² - 4*a*c} }/2*a

Substituting in the values correctly we would be left with

t = 56/2*a

= 56/32 =1.75sec