Question

Factorise- 1) (x-3)square - 7 (x-3)+10
2) 2x+4y-8xy-1

Answer 1

1) (x-3)^2 - 7 (x-3) + 10
= x^2 + 3^2 - 2*x*3 - 7x + 21 +10
= x^2 + 9 - 6x - 7x +31
= x^2 -13 x +40
= x ^2 - 8x - 5x + 40
= x( x - 8) - 5 (x -8)
= x- 8 = 0 and x-5 = 0
= x = 8 and x = 5

2)2x+4y-8xy-1
= 2x - 8xy -1 +4y
= 2x(1-4y) - 1 ( 1- 4y)
= 2x -1 = 0 and 1- 4y = 0
= 2x = 1. and. 1. = 4y
= x = 1/ 2. and y = 1/ 4