Question 193236
I'm having a little trouble with this problem:  Brent throws an object downward with initial velocity of -10 feet per second. The object travels a distance {{{ s = 16t^2-vt+h }}} ,where h = height in feet, v = initial velocity, s = initial height in feet, and t = time in seconds. If Brent is standing on a cliff 31.5 feet above the ground, in how many seconds will the object reach the ground?
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{{{s = -16t^2-vt+h }}} in general
{{{s = -16t^2-10t+31.5 }}} for this situation
Set s = 0
{{{16t^2+10t-31.5 = 0}}}
t = 9/8 seconds = 1.125 seconds