Answer
$(x-7)^2$
Work Step by Step
RECALL:
A perfect square trinomial can be factored using either of the following formulas.
(i) $a^2+2ab+b^2=(a+b)^2.$
(i) $a^2-2ab+b^2=(a-b)^2.$
The given perfect square trinomial can be written as
$x^2-2(x)(7)+7^2.$
Factor using formula (ii) above with $a=x$ and $b=7$ to obtain
$(x-7)^2.$
