Find the missing value so that the two points (-1, -1) and (x, 1) have a slope of 217. 6
7
10
12

6

Step-by-step explanation:

you needed to make a graph and then find the (-1,-1) and then move two spaces to the right and then seven up and you get (6,1)

hope this helped

If you would like a list of the steps/formula, message me and I'll send it to you as it's too long to post here. The answer to your question would be a21 = 162.

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