Factorise.

2x² + x – 45

On comparing with standard quadratic equation that is

we have,

a = 2, b = 1 and c = – 45

Now here,

Product a × c = 2 × – 45 = 90

Factors of 90; 1 × 90; 2 × 45; 10 × 9; 30 × 3

Sum should be b = 1

From above factors ( + 10x – 9x)

will give + x sum

therefore + x is replaced by ( + 10x – 9x)

Now above eq. becomes

; taking 2x and – 9 common

(x + 5)(2x – 9)