Final answer:
To factor the expression completely, first factor out any common factors and then factor the quadratic expression.
Step-by-step explanation:
To factor completely the expression -5x²y + 10xy - 15xy², we first look for a common factor among the coefficients. In this case, the common factor is 5. We can factor out the common factor 5 from each term:
-5x²y + 10xy - 15xy² = 5xy(-x² + 2x - 3y)
Now, we can factor the quadratic expression -x² + 2x - 3y. This expression can be factored into two binomials:
-x² + 2x - 3y = -(x - y)(x - 3y)
Putting it all together, the completely factored expression is:
-5x²y + 10xy - 15xy² = 5xy(x - y)(x - 3y)