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

9514 1404 393

  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.

both equations and proportions are better.