How do you factorise x^2 - 9.

1 answer:

4 0

X ^ 2 - 9

= x ^ 2 - 3 ^ 2

It turns into 3 ^ 2
Because 3 ^ 2 = 9

The final answer is
= ( x + 3 )( x - 3 )

remember the formula :

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

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Step-by-step explanation:

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