Answer
$y=7/25$
Work Step by Step
We need a common denominator (bottom of the fraction) to add the numerators (tops of the fractions). Thus, we multiply $\frac{5y}{1}$ by $\frac{5}{5}$ to get $\frac{25y}{5}$. (This is legal because $\frac{5}{5}$ is equal to one).
We now have:
$\frac{25y}{5}$-$\frac{3}{5}$=$\frac{4}{5}$
We subtract the numerators to obtain:
$\frac{25y-3}{5}$=$\frac{4}{5}$
To cancel out the two denominators, we multiply both sides of the equation by 5 to get that $25y-3=4$. We add 3 on both sides and then divide by 25 to obtain that $y=7/25$.