Question

(10x-7)2=
(10x+6(10x-6)
(1+4y)(1-4y)
pfff

Answer 1

a)
= (10x - 7)²
= 100x² - 2.10x.7 + 49
= 100x² - 140x + 49

b)
= (10x + 6).(10x - 6) 
= 100x² - 60x + 60x - 36
= 100x² - 36

c)
= (1 + 4y).(1 - 4y)
= 1 - 4y + 4y - 16y²
= 1 - 16y²