Answer
See below.
Work Step by Step
The function is linear because it is in the form $g(x)=mx+b$. At $x=-2$, the value is: $g(-2)=-4-2(-2)-4+4=0$.
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.