Question

If 3x² – kx – 15 = (3x – 5)(x + 3), the value of k is ______.

पर्याय

• 4

• – 4

• 3

• – 3

Answer 1

If 3x² – kx – 15 = (3x – 5)(x + 3), the value of k is – 4.

Explanation:

Given

3x² – kx – 15 = (3x – 5)(x + 3)

= 3x(x + 3) – 5(x + 3)

= 3x² + 9x – 5x – 15

= 3x² + 4x – 15

On comparing the coefficient of x on both sides;

`\implies` – k = 4

`\implies` k = – 4