Question 147609
{{{7x(x-15)=-252}}} Start with the given expression.



{{{7x^2-105x=-252}}} Distribute.



{{{7x^2-105x+252=0}}} Add 252 to both sides.



{{{7(x-12)(x-3)=0}}} Factor the left side 




Now set each factor equal to zero:

{{{x-12=0}}} or  {{{x-3=0}}} 


{{{x=12}}} or  {{{x=3}}}    Now solve for x in each case



So our answers are 


 {{{x=12}}} or  {{{x=3}}}