Answer: Choice C
Point D is 8 units to the left of point G
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Explanation:
Refer to the diagram below. I've graphed both points on the same xy grid. We can draw a horizontal line through points D and G to form a number line of sorts. Count the number of spaces along this number line to go from G to D. You should count 8 spaces to the left.
Effectively, this is the same as drawing a number line and plotting -10 and -2 on this number line. We only worry about the x coordinates of the two points since the y coordinates are the same (both are y = -3). Note how -10 is eight units to the left of -2 on the number line.