Question 147058
Suppose Charlie O' Brian hits a baseball straight upward at 150 ft/sec from a height of 5 ft. Use the formula to determine how long it takes the ball to return to the earth. Use the graph on the next page to estimate the maximum height reached by the ball. 
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Assume the formula is: h = -16t^2 + 150t + 5; where h = height and t = time (sec)
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Find the value of t when h = 0
-16t^2 + 150t + 5 = 0
Use the quadratic formula to find t:
{{{t = (-150 +- sqrt(150^2 - 4 * -16 * 5 ))/(2*-16) }}}
Do the math here and you should get a positive solution
t = 9.40821 sec for the ball to hit the earth
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The graph:
{{{ graph( 300, 200, -6, 12, -50, 400, -16x^2+150x+5) }}}
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You can estimate from this, that the max height is about 360 ft
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