Answer
$(a-10b)(a-8b)$
Work Step by Step
$(a+mb)(a+nb)=a^{2}+(m+n)ab+(mn)b^{2}$
$a^{2}-18ab+80b^{2}=$
Searching for two factors of $+80$ whose sum is $-18,$
we find$\qquad-10$ and $-8$
= $(a-10b)(a-8b)$
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.