There are two important things to know about a linear expression. First, it is an expression; it combines numbers and variables using at least one operation, but it contains no equal sign or greater than or less than symbols.
Another way to put it is that an expression is not a complete mathematical sentence. So 5 + d is an expression, but 5 + d = 7 is not.
Second, a linear expression is linear. There are no exponents in the expression that are greater than one. Though 5 + d is a linear expression, 5 + d2 is not.
It’s possible to write linear expressions in multiple ways; it depends on what part of the linear expression you want to emphasize. You can also write a linear expression in different ways to help you understand equivalent relationships. That’s particularly useful in looking at the relationships among fractions, decimals, and percentages.
As you work through this lesson, be aware of how you are using your time and how you are meeting your goals. Having the 21st century skill to manage your goals and your time will help you work carefully and efficiently. If you are not sure of a goal, reread the information on the slate. To the extent possible, avoid letting your mind wander. Devoting 100% of your attention to the work at hand can make a difference in how well—and how quickly—you master the material.
In summary, the two important things to know about a linear expression are:
1. It is an expression that combines numbers and variables using at least one operation, but it does not contain an equal sign or greater than/less than symbols. It is not a complete mathematical sentence.
2. It is linear, meaning it does not have exponents greater than one. It only contains variables raised to the power of one or constants.