Question

Factor completely 18x2 − 21x −15.

Answer 1

3(6x² + 3x - 10x - 5)
= 3(3x(2x + 1) - 5(2x + 1))
= 3(2x + 1)(3x - 5)

Answer 2

The factors of equation
`18x^2-21x-15` is
`=3((3x-5)(2x+1))`

Explanation:

Given : Equation
`18x^2-21x-15`

We have to factorize the given equation
`18x^2-21x-15`

Consider the given equation
`18x^2-21x-15`

Taking 3 common from each term, we have,

`=3\left(6x^2-7x-5\right)`

We will solve the given equation using middle term split method,

-7x can be written as 3x -10x

Equation becomes,

`=3(6x^2+3x-10x-5)`

Taking 3x common from first two term and -5 common from last two terms, we have,

`=3(3x(2x+1)-5(2x+1))`

Taking (2x+1) common, we have,

`=3((3x-5)(2x+1))`

Thus, The factors of equation
`18x^2-21x-15` is
`=3((3x-5)(2x+1))`