Question

factorise using suitable identity- 49x^2 - 9^2

Answer 1

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• Factorise using suitable identity.

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We know that,

${x}^{2} - {y}^{2} = (x + y)(x - y)$

So,

$49 {x}^{2} - {9}^{2}$

$= {(7x)}^{2} - {(9)}^{2}$

Applying this identity, we get,

$= (7x + 9)(7x - 9)$

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• $(7x + 9)(7x - 9)$

Answer 2

Answer:

49x²-9²

If the value of a² is 49x so the value of a will be 7x.

And the value of b² is 9 so value of b will be 3.

so using property:

(a+b) (a-b)

Put the values on correct places.

(7x+3)(7x-3)