Answer:
Step-by-step explanation:
First off, your polynomial should be a third degree, not a second degree. That's probably why you didn't get someone to answer this for you already.
If x + 2k is a factor of that polynomial, then by the Zero Product Property
x + 2k = 0 and x = -2k. That means that, by the factor theorem, f(-2k) = 0 (which means that if you plug -2k in for all the x's you get a zero). Therefore,
[tex]3(-2k)^3+6k(-2k)^2-14(-2k)-3=0\\-24k+24k+28k-3=0\\28k-3=0\\28k=3\\k=\frac{3}{28}[/tex]
