Question

If x = -1/2 is a root of the quadratic polynomial equation 3x^2+kx-3=0 , then find the value of k

Answer 1

Answer:

x = -1/2

3x² +kx -3=0

3(-1/2)²+k(-1/2)-3=0

3/4- k/2 - 3 =0

Take LCM 4

-2k - 8 =0

k = -4

Answer 2

Step-by-step explanation:

x = -1/2

3x² + kx - 3 =0

3(-1/2)² + k(-1/2) -3 = 0

3(1/4) -k/2 -3 = 0

3/4 - k/2 - 3 = 0

(3 - 2k - 12)/4 =0

3 - 2k - 12 = 0

-9 = 2k

k = -9/2