Question 154712
{{{x(x-7)=30}}}
then
{{{ x^2-7x-30=0 }}}
then
{{{x = (-(-7) +- sqrt( (-7)^2-4*(1)*(-30) ))/(2*1) }}}
then 
{{{x =( 7 +- sqrt( 169 ))/2 }}}
then
{{{x = (7 +- 13)/2 }}}
then
x=-3 or x=10