
Example: Factorise 81  (xy)^{2}. Solution: Given that 81  (xy)^{2} = (9)^{2}  (xy)^{2}. The expression is a difference of two squares. = [9 + (xy)] [9  (xy)] Therefore factors of [81  (xy)^{2}] = [9 + (xy)] [9  (xy)] Directions: Find the factors of given expressions and show your work. Also write at least ten examples of your own. 