The factored form is

To factor the quadratic expression
, we can look for two binomials in the form
,
where a and b are constants. The square of this binomial will have the desired quadratic expression.
Let's factor the given expression:

This expression can be factored into the square of a binomial.
The binomial will have the form 4x−9y, since

So, the factored form is:

Alternatively, you can expand
to verify that it equals the given expression.
Question
Factor the expression {eq}16x^2 - 72xy + 81y^2 {/eq} into a product of binomials.