math problem
posted by Lavern on .
please help
Factor completely
144b^2+648bg+729g^2

start by pecking away common factors
144b^2+648bg+729g^2
= 9(16b^2 + 72bg + 81g^2)
ahh, looks like perfect squares at front and back
could (4b + 9g)^2 give us a middle term of 72 bg ??
2(4)(9) = 72 , yeaaaahhh!
= 9(4b+9g)^2