Been a while since I've done this, but I think I remember what to do here:
The main technique is called "rise over run." The first number, the rise, is how far up the next dot on the right should be. The other number, the run, is how many spaces right the dot should be at. 1+(-2)=-1 and 8+3=11. The next dot on the right should be placed at (11,-1). If you're looking on the left, replace the addition with subtraction. 1-(-2)=3 and 8-3=5. The dot on the left should be (5,3). This means that the three dots on the slope are, in order, (5,3), (1,8), and (11,-1). To find the numbers after the third dot and before the first dot, simply repeat their respective equations.
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