Question

Zeroes of the polynomial $x^2$-4x-21 are

• A. -3, -7
• B. 3, 7
• C. -3, 7
• D. 3, -7

Answer 1

The correct option is C

-3, 7

$x^2$ - 4x - 21 = $x^2$ + 3x – 7x – 21

= x (x + 3) -7 (x + 3)

= (x + 3) (x - 7)

Zeroes of the polynomial are 7, -3