Question

Factor the expression 4b4 − 144 using the polynomial identity (x2 − y2) = (x − y)(x + y).

Answer 1

So we need a perfect square. The "O" and "I" values in the FOIL method will cancel leaving you with an exponent and a negative integer. Look for the square root of both expressions.

4b^4 - 144 =
(2b^2 - 12)(2b^2 + 12)

Answer 2

4b^4=(2b^2)^2
144=(12)^2

(2b^2)^2-(12)^2=(2b^2-12)(2b^2+12)