Question

factorise 100 - r2. please answer ​

Answer 1

(10+r)(10-r)

is the factorised answer, with which r can also be found

using the identity,

(a+b)(a-b)

Answer 2

Answer:

it can also written as10^2-r^2

=====(10-r)(10+r)

by identity a^2-b^2=(a-b)(a+b)