Question

If –5 is a root of the quadratic equation 2x² + px – 15 = 0, then:

Options

• p = 3

• p = 5

• p = 7

• p = 1

Answer 1

p = 7

Explanation:

Since – 5 is a root of the equation 2x² + px – 15 = 0

∴ 2(-5)² + p(–5) – 15 = 0

⇒ 50 – 5p – 15 = 0

⇒ 5p = 35

⇒ p = `35/5`

⇒ p = 7