Answer & Step-by-step explanation:
To find if they have a constant of proportionality of 12, use the following:

Divide y by the x value (x,y), and if the remaining equation is true, then that table has a constant of proportionality of 12.*
:Done
*Make sure you check all the values in a table. Sometimes only the first values will have k=12, while the others don't.
**The constant of proportionality is represented by <em>k</em>.
Answer: d
Step-by-step explanation: because every x has 1 y
X/4 = 2.....x = 8
x - 9 = 17....x = 26 <=== there is the odd ball
x + 12 = 20....x = 8
2x = 16....x = 8