Answer: -4/15
Step-by-step explanation: To add these two fractions together,
we start by finding their Least Common Denominator (LCD).
Since our denominators of 5 and 3 have no factors in common,
our least common denominator is 5 · 3 or 15.
In order to get a denominator of 15 in each fraction,
we multiply top and bottom of the first fraction by 3
and top and bottom of the second fraction by 5.
That gives us -9/15 + 5/15 which simplifies to -4/15.
As your last step, make sure that the fraction
that you end up with doesn't reduce.
In this case, -4/15 does not reduce but watch out for this last step.