Question 132015


{{{t^2-5t-36=0}}} Start with the given equation


{{{(t-9)(t+4)=0}}} Factor the left side (note: if you need help with factoring, check out this <a href=http://www.algebra.com/algebra/homework/playground/change-this-name4450.solver>solver</a>)




Now set each factor equal to zero:

{{{t-9=0}}} or  {{{t+4=0}}} 


{{{t=9}}} or  {{{t=-4}}}    Now solve for t in each case



So our answer is 

 {{{t=9}}} or  {{{t=-4}}} 



Notice if we graph {{{y=x^2-5x-36}}}  (just replace t with x)  we can see that the roots are {{{x=9}}} and  {{{x=-4}}} . So this visually verifies our answer.



{{{ graph(500,500,-10,10,-10,10,0, x^2-5x-36) }}}