Question

find the value of k if -2 is a root of the quadratic equation kx²+x-10=0

Answer 1

Hope it will help you friend

Answer 2

Answer:

The value of k is, 3

Explanation:

The quadratic equation: g(x)= $kx^2+x-10=0$.

The real number x=p is the root of the polynomial f(x) if and only if f(p)=0.

Given: -2 is the root of the g(x)= $kx^2+x-10=0$ or x =-2 is the root of the polynomial g(x)

then,

$g(-2)=k(-2)^2+(-2)-10$

$4k-2-10=0$  or

4k-12=0  or

4k=12

Divide both sides by the same number i.e, 4 we have

$\frac{4k}{4}= \frac{12}{4}$

On simplify we have;

k=3

Therefore, the value of k is, 3