Question

Pls help !! this is due today
2x^2-7x-9=6 solve my factoring but cannot factor by grouping

Answer 1

x = -
`(3)/(2)`, x = 5

Explanation:

Given

2x² - 7x - 9 = 6 ( subtract 6 from both sides )

2x² - 7x - 15 = 0

Consider the factors of the product of the coefficient of the x² term and the constant term which sum to give the coefficient of the x- term.

product = 2 × - 15 = - 30 and sum = - 7

The factors are - 10 and + 3

Use these factors to split the x- term

2x² - 10x + 3x - 15 = 0 ( factor the first/second and third/fourth terms )

2x(x - 5) + 3(x - 5) = 0 ← factor out (x - 5) from each term

(x - 5)(2x + 3) = 0

Equate each factor to zero and solve for x

2x + 3 = 0 ⇒ 2x = - 3 ⇒ x = -
`(3)/(2)`

x - 5 = 0 ⇒ x = 5

Answer 2

x=
`-(3)/(2),5`

Explanation:

Factor and set each factor equal to zero.