Final answer:
To simplify the expression u + 6u + -5u, combine the like terms to get 2u.
Step-by-step explanation:
To simplify the given expression, u + 6u + -5u, you need to combine the like terms. The like terms are those that have the same variable raised to the same power. In this case, all the terms have the variable 'u' raised to the power of 1. So the simplified expression is (1 + 6 - 5)u, which simplifies further to 2u.
Learn more about Combining like terms in an algebraic expression