Question

Find k, if x= 2 is a root of the
equation k x²+5x+6=0​

Answer 1

Answer:

k = -4

Step-by-step explanation:

Answer 2

Solution :

Given:

• x = 2
• P(x) =Kx^2 +5x+6 = 0

If a is a root of the polynomial P(x) then P(a) = 0

Using the same principle above we can find value of k.

P(x) = kx^2 +5x+6=0

P(2) = 4k +10 +6 = 0

or , 4k +16 = 0

or, 4k = -16

or, K = -4

Verification: by putting k = -4 in P(x).

P(x) = kx^2 +5x+6

or, P(x) = -4x^2+5x + 6

Putting Value of x = 2

P(2) = -4x4 +10 +6

or, P(2) = -16 +16

or, P(2) = 0

Hence, value of k is correct.