Answer:
yes, no, yes, no
Explanation:
For it to be a line, that means that when x goes up by 1 y goes up by the same thing every time.
7a. from (1, 12) to (2, 8), the x coordinate goes up by 1 and the y coordinate goes down by 4. From (2, 8) to (3, 4) the y coordinate again goes down by 4 when the x coordinate goes up by 1. This pattern continues for the other points, so yes.
Do the same thing for the rest and you should get:
7b. No
7c. Yes
7d. No