You divide 18 with 3 and is going to equal 6 so that should be your constant proportionality
-n/3=4
-n/3 x 3=4 x 3
-n=12
-n/-1=12/-1
n=-12
Since your probably solving for W, isolate W by adding the -3n to both sides and get W=5n now use a calculator and multiply 5 and Pi. To Get 15.7.
I used N for pi since I don’t have that symbol
You need to specify what needs to be solved so I just assumed W
I can't see the whole graph
