Question

if x+1 is a factor of polynomial 5X²+kx, then the value of k is?​

Answer 1

Step-by-step explanation:

Given -

• x+2 is a factor of 5x²+kx+1

To Find -

• value of k

As we know That :-

• if x+2 is a factor of polynomial then x = -2 is zero of that polynomial

➩ p(x) =5x²+ Kx + 1 = 0

➩ p(-2) = 5 (-2)² + k + 1 = 0

➩ 20 -2k + 1 = 0

➩ 2k = 21

➩ k = 21/2

Hence,

The value of k is 21/2

Verification :-

➩ 5x² + 21x/2 +1

➩ 10x² + 21x + 2

➩ 10x² + 20x + x + 2

➩ 10x(x+2) + 1(x+2)

➩ (10x+1) (x+2)

Here the factor, comes true same as given in the question.

It shows That our answer is absolutely

correct.

Answer 2

x + 1 = 0

x = -1

then ,

5(-1)² + k(-1) = 0

5 - k = 0

k = 5

• Value of k is 5