Question

Factorise 9(2a-b)2-4(2a-b)-13

Answer 1

Let the value of 2a-b be x. Then
A.T.Q.

9x²-4x-13------------------------1
By factorising method
9x²-13x+9x-13
x×(9x-13)+1×(9x-13)
(x+1)(9x-13)
From Equation 1
[2a-b+1][9×(2a-b)-13]
[2a-b+1][18a-9b-13]

Answer 2

Given:

$9(2a-b)^2-4(2a-b)-13=0$

To Find:

Value after factorization = ?

Solution:

Let (2a-b) be "x".

Now,

⇒ $9x^2-4x-13=0$...(equation 1)

⇒ $9x^2+9x-13x-13=0$

⇒ $9x(x+1)-13(x+1)=0$

⇒ $(x+1)(9x-13)=0$

From (equation 1), we get

⇒ $[2a-b+1][9(2a-b)-13]$

⇒ $(2a-b+1)(18a-9b-13)$

So that the correct answer is "(2a-b+1)(18a-9b-13)".