The correct question is
What is the simplified form of sqrt (144 x^36) ?
144=(2^4)*(3^2)
then
sqrt (144 x^36)=sqrt (144)*sqrt (x^36)
sqrt (144)=sqrt ((2^4)*(3^2))=2² * 3=12
sqrt (x^36) =x^(36/2)=x^18
therefore
sqrt (144 x^36)=sqrt (144)*sqrt (x^36)=12*x^18
the answer is 12*x^18
