Question 158886
Same as with numbers.
You must have the same denominator.
Here's an example.
{{{5/x+3/(x+3)=(5(x+3))/(x(x+3))+(3x)/(x(x+3))}}}
{{{5/x+3/(x+3)=(5(x+3)+3x)/(x(x+3))}}}
{{{5/x+3/(x+3)=(5x+15+3x)/(x(x+3))}}}
{{{5/x+3/(x+3)=(8x+15)/(x(x+3))}}}