Question

(i) (28)+(-15) + (-13)
15. Give possible expressions for the length and breadth of each of the following
rectangles, in which their areas are given:
Area : 35y + 13y -12
Area : 25a - 35a + 12​

Answer 1

$1. }35 {y}^{2} + 13y - 12 \\ = 35 {y}^{2} + 28y - 15y - 12 \\ = 7y(5y + 4) - 3(5y + 4) \\ = (7y - 3)(5y + 4) \\ length = 7y - 3 \\ breadth = 5y + 4$

2.

$25 {a}^{2} - 35a + 12 \\ = 25a ^{2} - 20a - 15a + 12 \\ = 5a(5a - 4) - 3(5a - 4) \\ = (5a - 4)(5a - 3) \\ length = 5a - 3 \\ breadth = 5a - 4$