Factor:

4b2 - 12b + 9

(2b-3) ²

Step-by-step explanation:

The square of a binomial is ...

(p - q) ² = p² - 2pq + q²

The fact that the first and last terms are perfect squares suggests that you might want to look to see if the middle term matches this form. It does.

For p² = 4b², p=2b.

For q² = 9, q = 3.

Then 2pq = 2 (2b) (3) = 12b.

So, the factoring is ...

4b² - 12b + 9 = (2b - 3) ²