Final answer:
Simplifying algebraic expressions requires combining like terms and following arithmetic rules. Multiplication signs between same signs give a positive, and different signs result in negative outcomes. Checking the answer for reasonability ensures accuracy.
Step-by-step explanation:
To simplify algebraic expressions, combine like terms and simplify operations of a according to the order of operations and properties of arithmetic. Multiplication of numbers with the same sign results in a positive product, while numbers with opposite signs result in a negative product. Utilize these basic principles to simplify each expression provided. Remember to check that the simplified answer is reasonable and accurate.