Well using distance formula

The answer I got was Distance = 45.9 what ever unit of measure it might ask for. Feel free to check my math just in case.
Answer:
28 m
Step-by-step explanation:
The longer side can be found using the Law of Cosines. The semi-diagonals are of length 12 and 20 m, and the angle between them facing the long side is 180° -60° = 120°.
c^2 = a^2 +b^2 -2ab·cos(C)
c^2 = 12^2 +20^2 -2·12·20·cos(120°) = 144 +400 +240 = 784
c = √784 = 28
The longer side is 28 meters.
28,000+3,000x=36,000+2,000x
X will be the number of years worked, now we just have to make the equation true.
I did the work out already, and the answer is 8!
If you want to check my answer just substitute it in to the problem for x.