Question

factorise(i) 5-20x^2
(ii)a^2-b^2-a-b​

Answer 1

!. 5(1-4x^2)

2. a^2-a-b^2-b

= a(a-1)-b(b+1)

Answer 2

$5 - 20x ^{2}$

$5(1 - 4x^{2} )$

$5((1) ^{2} - (2x) ^{2} )$

$5(1 + 2x)(1 - 2x)$

2nd answer....

$a ^{2} - b^{2} - a - b$

$(a + b)(a -b) - 1(a + b)$

$(a + b)(a - b - 1)$