a) x2 +2xy + x + 2y
= (x2 +2xy) + (x + 2y)
= x(x + 2y) + (x + 2y)
= (x + 2y)(x + 1)
b) 7x2 - 7xy - 5x + 5y
= (7x2 - 7xy) - (5x - 5y)
= 7x(x - y) - 5(x - y)
= (x - y)(7x - 5)
c) 3(x + 2) - y(x + 2)
= (x + 2)(3 - y)
d) 5(x - 3) + y(3 - x)
= 5(x - 3) - y(x - 3)
= (x - 3)(5 - y)
e) (x2 - 8)2 + 36
= x4 - 16x2 + 64 + 36
= x4 - 16x2 + 100
= x4 + 20x2 - 36x2 + 100
= (x4 + 20x2 + 100) - 36x2
= (x2 + 10)2 - (6x)2
= (x2 + 10 - 6x)(x2 + 10 + 6x)