Combine and .

Add to both sides of the equation.

Combine the numerators over the common denominator.

Add and .

Since the expression on each side of the equation has the same denominator, the numerators must be equal.

Divide each term in by .

Cancel the common factor of .

Cancel the common factor.

Divide by .

Divide by .

Solve for f 3/5f-4/5=2/5