Respuesta :
[tex]\bf \textit{difference of squares}
\\ \quad \\
(a-b)(a+b) = a^2-b^2\qquad \qquad
a^2-b^2 = (a-b)(a+b)\\\\
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%a^2-121
a^2-121\qquad \qquad \boxed{121=11^2}\qquad a^2-11^2\implies (a-11)(a+11)[/tex]