Answer
$49-84p+36p^2$
Work Step by Step
Using $(a+b)^2=a^2+2ab+b^2$ or the square of a binomial, the given expression, $
(7-6p)^2
$, is equivalent to
\begin{array}{l}\require{cancel}
(7)^2+2(7)(-6p)+(-6p)^2
\\\\=
49-84p+36p^2
.\end{array}