Question 116934
{{{s = 16t^2 + 32t}}}
{{{s = 149}}}ft
{{{149 = 16t^2 + 32t}}}
{{{16t^2 + 32t - 149 = 0}}}
Use the quadratic formula
{{{t = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}}
when equation is in the form
{{{ax^2 + bx + c = 0}}}
{{{a = 16}}}
{{{b = 32}}}
{{{c = -149}}}
{{{t = (-32 +- sqrt( 32^2-4*16*(-149) ))/(2*16) }}}
{{{t = (-32 +- sqrt(10560))/32 }}}
{{{t = (-32 +- 102.762)/32 }}}
{{{t = -1 +- 3.2}}}
{{{t = 2.2}}}sec answer
{{{t = - 4.2}}} reject this solution
It will take the ball 2.2 sec to fall 149 ft