Question

the factorisation of m2-81​

Answer 1

Step-by-step explanation:

Rewrite 81 as 92 . Since both terms are perfect squares, factor using the difference of squares formula, a2−b2=(a+b)(a−b) a 2 - b 2 = ( a + b ) ( a - b ) where a=m and b=9 .

Answer 2

Answer:

(m+9)(m-9)

Step-by-step explanation:

Identity used – a² - b² = (a+b)(a-b)

m² - 81

= m² - (9)²

= (m+9)(m-9)