Question

Find the value of 'K'for which X=-2 is a root of the quadratic equation Kx2+x-6=0 .​

Answer 1

Substitute x = -2 in the quadratic equation.

k(-2)^2 +(-2) - 6 = 0

4k - 2 - 6 = 0

4k = 6 + 2

4k = 8

k = 8 ÷ 2

k = 4

THEREFORE, K IS EQUAL TO 4

Answer 2

Answer:

IF X = -2 THEN ,

K(-2)2 + (-2)- 6 = 0

-4K -2 -6 = 0

-4K -8 = 0

-4K = 8

THEREFORE , K = 8/-4 = -2

VERIFICATION

-2 (-2)2 -2-6 = 0

4 (2) - 8 = 0

THEREFORE , 8 - 8 = 0