The expression 4x/5-2x/3 is equivalent to?

This is so harddd! solve. 1 + 1 = solve 4 + 4 = solve 3 x 3

Need ! give step by step solutions on how to solve number one \frac{9-2\sqrt{3} }{12+\sqrt{3} } number two x+4=\sqrt{13x-20} number three (domain and range) f(x)=2\sqrt[3]{x} +1

The solution set for 5v2 – 125 = 0 is