Question

Write the following as a product of factor: 

x(2x + 5) – 3

Answer 1

Given expression: x(2x + 5) – 3 = 2x² + 5x – 3

We have to find two numbers whose sum is 5 and whose product is –6.

These numbers are 6 and –1.

Now, using middle term factorisation method,

2x² + 5x – 3

= 2x² + 6x – x – 3

= 2x(x + 3) – (x + 3)

= (x + 3) (2x – 1)

The factorisation result is (x + 3) (2x – 1).