Question

8.
If one zero of the quadratic polynomial x2 - 7x + 5k is -2, then find the value of k
​

Answer 1

k = - 3.6

Explanation:

Given x = - 2 is a zero then f(- 2) = 0

Substitute x = - 2 into the polynomial and equate to zero

(- 2)² - 7(- 2) + 5k = 0

4 + 14 + 5k = 0

18 + 5k = 0 ( subtract 18 from both sides )

5k = - 18 ( divide both sides by 5 )

k = - 3.6