Question

find the value of k, if (x+3) is factor of 3x^2+kx+6.

Answer 1

If x+3 is a factor of the given equation then x = -3 must satisfy the equation.

Substituting the value x = -3 we get,

3(-3)^2 -3k + 6 = 0
3k = 33
k = 11

Answer 2

Answer:

Value of k = 11

Step-by-step explanation:

Factor Theorem:

" If (x-a) is a factor of a polynomial p(x) then p(a) = 0"

Here ,

Let p(x) = 3x²+kx+6

if (x+3) is a factor of p(x) then p(-3) = 0

=> p(-3) = 3(-3)²+k(-3)+6 = 0

=> 27-3k+6 =0

=> -3k+33=0

=> -3k = -33

Divide both sides by (-3), we get

=> k = 11

Therefore,

Value of k = 11

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