Notice that there are three known coordinates: (−9, −4), (0, 2), and (3, 4).
Now notice that for every difference of 3 in the
x-coordinate, the y-coordinate changes by 2.
Use this reasoning to fill in the rest of the table.
The difference in the y-coordinate from x = 0 to x = 3 is 2. Since 6 is twice 3, the difference in the y-coordinate from x = 0 to x = 6 is twice as much.
(−6, −2) and (6, 6)
To find the rule, look for a pattern that can relate the
y-coordinate to the x-coordinate.
Notice that at x = 0, y = 2.
Also remember that the y-coordinate increases by 2 for every 3 units the x-coordinate increases.
The slope describes how the values increase.
It can be written as:
You can fill in the last y-coordinate in the table by substituting 1 into the rule.
If you were to graph all of the points in the table, would they form a line?
Complete the table in the eTool below to graph the points.
Click the link at right for the full version of the eTool: CC3 8-127 HW eTool