What grade you in and what unit lesson is this, I might be able to help you. I go to the same school.
Plug any number in for x and find the resulting y, then if you need to graph place the coordinate points on the plane. For example if you set x=2 the equation becomes y=0.5(2). From here we can see 0.5(2)=1 and this is equal to 1 so in a data chart you would write under x the number 1 and under y the number 2.
The answer is 73 because 8 is more than 5 so it rounds up to be 73