Question

split the middle term x2 + 6a - 91

Answer 1

Note: your question is incorrect.. It should be x^2 + 6x - 91.

Given Equation is x^2 + 6x - 91

⇒ x^2 - 7x + 13x - 91

⇒ x(x - 7) + 13(x - 7)

⇒ (x + 13)(x - 7)

Hope it helps!

Answer 2

Your question needs a correction,

Correct question : x^2 + 6x - 91

⇒ x^2 + 6x - 91

Splitting 6x in two terms such that the product of their numerical coefficient  becomes 91.

6x = 13x - 7x , and product of 13 and 7 is 91

⇒ x^2 + ( 13 - 7 ) x - 91

⇒ x^2 + 13x - 7x - 91

⇒ x( x + 13 ) - 7( x + 13 )

⇒ ( x + 13 )( x - 7 )

∴ x^2 + 6x - 91 = ( x + 13) ( x - 7 )

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