Sorry if this is a silly question, but can anyone algebraically explain to me how these two equations are equivalent.

Question

360/(180-x)=y
(-360+180y)/x=y

Desmos shows that they're the same line: attps://www.desmos.com/calculator/7nkhupilpc and replace a with h if you want to see graph.

Answer 1

clear fraction in 1st eqn. (multiply by 180-x) ... 360 = 180 y - xy
... add xy ... 360 + xy = 180 y

substitute into 2nd eqn. ... [-360 + (360 + xy)] / x = y
... multiply by x ... -360 + 360 + xy = xy
... the 360's cancel ... xy = xy