158k views
0 votes
Solve the quadratic equation 2x
x^(2) \\ -4x-6=0

User DTYK
by
7.4k points

1 Answer

5 votes

Answer:

x = - 1 , x = 3

Explanation:

given the quadratic equation

2x² - 4x - 6 = 0 ( divide through by 2 )

x² - 2x - 3 = 0

To factorise , consider the factors of the constant term (- 3) which sum to give the coefficient of the x- term (- 2)

the factors are + 1 and - 3 , since

+ 1 × - 3 = - 3 and + 1 - 3 = - 2

use these factors to split the x- term

x² + x - 3x - 3 = 0 ( factor the first/secnd and third/fourth terms )

x(x + 1) - 3(x + 1) = 0 ← factor out (x + 1) from each term

(x + 1)(x - 3) = 0 ← in factored form

equate each factor to zero and solve for x

x + 1 = 0 ( subtract 1 from both sides )

x = - 1

x - 3 = 0 ( add 3 to both sides )

x = 3

solutions are x = - 1 , x = 3

User Ariel Popovsky
by
7.4k points