Question

If x = –2 is one of the solutions of the quadratic equation x² + 3a – x = 0, then the value of ‘a’ is ______.

Options

• –8

• –2

• `-1/3`

• `1/3`

Answer 1

If x = –2 is one of the solutions of the quadratic equation x² + 3a – x = 0, then the value of ‘a’ is –2.

Explanation:

If x = –2 is a root,

Substitute into x² + 3a – x = 0: 

(–2)² + 3a – (–2) = 0

⇒ 4 + 3a + 2 = 0

⇒ 3a + 6 = 0

⇒ a = –2