Mary Lost 30 pounds. Before her diet she weigh 180 pounds. What is the percent of change 

16.7%

Step-by-step explanation:

150         x

=

180          100

150(100)=180(x)

15000=180x

180         180

x=83.3 repeated

100-83.3=16.7

yes because there is exactly one y value for every x value

for function there can't be more than one value for every x value