Answer :
[tex]\begin{gathered} x^2-10x=11 \\ x^2-10x-11=11-11 \\ x^2-10x-11=0 \\ (x+1)(x-11)=0 \\ x+1=0 \\ x+1-1=0-1 \\ x=-1 \\ \text{and} \\ x-11=0 \\ x-11+11=0+11 \\ x=11 \end{gathered}[/tex]
answer: x = - 1
x = 11