Question 1091385
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A linear function (which graphs as a straight line)
is one where the ratio of change/difference in y-coordinate
to the change/difference in x-coordinate
for a pair of points
is the same,
no matter what pair of points you choose.
The choices A, B, C, and D,
have the same x-coordinates,
the very conveniently spaced -2, 0, 2, and 4,
spaced 2 units apart,
and listed in increasing value of x-coordinate.
For a linear function, the y-coordinates
should be spaced evenly too,
either increasing, decreasing, or staying the same
from one ordered pair to the next one in the list.