Question

Find the zeroes of the quadratic polynomial and verify the relationship between the zeroes and the coefficients: 2x^2+11x+15

Answer 1

f(x) = 2x^2 ˗ 11x + 15

= 2x^2 ˗ (6x + 5x) + 15

= 2x^2 ˗ 6x ˗ 5x + 15  

= 2x (x ˗ 3) ˗ 5 (x ˗ 3)  

= (2x ˗ 5) (x ˗ 3)  

∴ f(x) = 0 ⇒ (2x ˗ 5) (x ˗ 3) = 0  

⇒ 2x ˗ 5= 0 or x ˗ 3 = 0  

⇒ x = 5/ 2 or x = 3  

So, the zeroes of f(x) are 5/2 and 3.

This is your answer.

Hope this helps you!

Step-by-step explanation: