help pls I'm not smart enough for this..

Answer:
Step-by-step explanation:
Number replaces with each corresponding value.
The number on the left is the x, and the number on the right of the colon is y.
Simply replace x and if you get the y, it is a match.
y = 1/2(2) = 1
y = 5(1) = 5
y = 1.5(16) = 16
y = 3(1) = 3