Answer:
it is a linear expression
Easiest way I could think of is choose a point in the gray area and use the X,Y to plug into the answers whichever one makes sense is correct.
For every input, there is one output
for every x there is one y
(x,y)
if x repeats with a differnt y, it's not a function
we see
(2,3) and (2,4) and all of them
no, not a function
<span>no, each ordered pair in this list has the same first element
answer is first one
</span>
28 is the LCM of 4 and 7 as 4*7 = 28