Answers

2015-03-03T15:25:52+05:30
1) x³ (2a-b) + x² (2a-b)
(2a-b) is common in both terms
Therefore, 
(2a-b)(x
³+x²)
(2a-b)(x²)(x+1)

2) 9a (3a-5b) - 12a² (3a-5b)

(3a-5b)(9a-12a²)
(3a-5b)(3a)(3-4a)

3) (x+5)² - 4 (x+5)

(x+5)(x+5-4)
(x+5)(x+1)
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