Question 242699
You were very close. Factor the numerator:
{{{((m+p)(m-p))/(p-m)}}}
The error was that (m-p) and (p-m) are not the same. You cannot cancel factors unless they are the same.<br>
But you may recognize that (m-p) and (p-m) are negatives of each other. (Think about this and it will make sense.) So if we factor out a -1 from one of them then we will have matching factors to cancel:
{{{((m+p)(m-p))/(-1)(m-p)}}}
which simplifies to
{{{(m+p)/(-1)}}}
or
{{{-m-p}}}