The given expression is a polynomial in terms of variables \(x\) and \(y\). To simplify this expression, we can combine like terms. The terms \(2xy\) and \(xy\) are like terms and can be combined.
Step 1: Identify Like Terms
The given expression is \(-3x^2 + 2xy + xy\). We identify the like terms, which are \(2xy\) and \(xy\).
Step 2: Combine Like Terms
Combine the like terms \(2xy\) and \(xy\) to get \(3xy\). The expression now becomes:
\[
-3x^2 + 3xy
\]
Step 3: Factor the Expression
Factor the expression \(-3x^2 + 3xy\) by taking out the common factor, which is \(3x\):
\[
3x(-x + y)
\]
Final Answer
The simplified and factored form of the expression is:
\[
\boxed{3x(-x + y)}
\]