Question

If one root of the quadratic equation 2x² + kx – 6 = 0 is 2, the value of k is:

Options

• 1

• –1

• 2

• –2

Answer 1

–1

Explanation:

Since x = 2 is a root of the equation 2x² + kx – 6 = 0

∴ 2(2)² +k(2) – 6 = 0

⇒ 8 + 2k – 6 = 0

⇒ 2k = –2

∴ k = –1