Question

What are the solution(s) for the quadratic equation?

Answer 1

Let's see

$\\ \rm\rightarrowtail x^2+12x+36=0$

$\\ \rm\rightarrowtail x^2+6x+6x+36=0$

$\\ \rm\rightarrowtail x(x+6)+6(x+6)=0$

$\\ \rm\rightarrowtail (x+6)(x+6)=0$

$\\ \rm\rightarrowtail x=-6$