Using the graph, predict the y-value when the x-value is 13
A) 17
B) 18
C) 19
D) 20

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Answer:
D) 20
Step-by-step explanation:
Each point marked on the graph is 3 units higher and 2 units to the right of the one before. The last dot is at x=9, so a dot at x=13 will be 2×2=4 units to the right. At the same rate of increase, it will be 2×3=6 units higher than 14.
The y-value is predicted to be 20 at x=13.