Question

Give zeroes of quadradic polynomial

x2
+ 2x – 15.​

Answer 1

Given quadratic polynomial: x^2 + 2x - 15

Step 1) Factorise the polynomial.

x^2 + 2x - 15

= x^2 - 3x + 5x - 15

= x(x-3)+5(x-3)

= (x-3)(x+5)

Step 2) Equate the expression obtained in step 1 with zero.

(x-3)(x+5)=0

For this to be true,

Either, x-3 = 0

=> x = 3

Or, x+5 = 0

=> x = -5

Thus, zeroes of the quadratic polynomial are 3 and -5.