I need help identifying the sides of this word problem:

Mr. Clark is finding his distance to a building across the river. He makes a turn of 90 degrees, measures off 45 meters, and finds the acute angle to be 80 degrees. Write the formula that shows about how far he is from the building.

When I try to solve this I use the tangent formula and got 255 meters but I am not sure if this is correct. Can you please help me out.

You're correct, from my interpretation of the question.