11. Find three diff erent pairs of factors that form the expression 40a − 80b 12. If 10x – 4 is a factor, fi nd the other factor if the product of the two factors is 100 x2
− 25ab y
(v) − 3m and 18 (vi) − 12ef and − 27fg
(iv) 10u − 10v (iv) 10x − 100y
(iv) (7x) (2x + 2y)
− 40x
13. Find two expressions, one for the length and one for the width, if the total area of a rectangle is represented by the expression 5 b2