**Video Transcript**

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Transcript
**Simplifying Variable Expressions**

**Algebraic expressions with more than one variable** can look scary. To make **variable expressions** easier to solve, simply simplify! Don't be frightened; I will walk you through the steps.

### You can only add and subtract like Terms

This expression has two different variables: 3x + 2y. Hmm… How do you **simplify** this expression? Maybe you're thinking 3x + 2y = 5xy. STOP! This is wrong! You can't simplify this expression anymore. Combining terms with x and terms with y is not possible.

It's almost as wrong as Dr. Evil attempting to create a “Sharkuine” – by combining a shark with a penguine! Just like sharks and penguins, variables such as x and y are not the same. Repeat to yourself: **You can only add and subtract like terms!** When adding and subtracting variables, **never, ever combine unlike terms**. Never, ever!

### Example how to simplify Variable Expressions

Let’s try out this example. We will go step by step. x + 3 · (10 + y) − 7x − y.

- Step 1 is to write out the expression as a sum. See the
**parentheses**? You will need to use the**Distributive Property**to multiply the three times the binomial contained inside the parentheses. Now you have: x + 30 + 3y − 7x − y. - Step 2 is to group the like terms. You can use the
**Commutative Property**to move the terms. Place the x’s with x’s, the y’s with y’s, and so on. This will make the next step easier: x − 7x + 3y − y + 30. - Now, Step 3 is to simplify the expression by combining the like terms. For terms that have numbers and variables, remember the coefficient tells us how many there are of each variable: −6x + 2y + 30.

Ok, let’s go over this one more time:

- Step 1:
**Write the expression as a sum.**If there are parentheses, use the**Distributive Property**. - Step 2: Move the terms around to
**group the like terms**by using the**Commutative Property**. - And lastly, Step 3,
**simplify the expression**by combining the like terms.

Most important: **Never, ever try to combine unlike terms.** Here is your reminder: Don’t create sharkuins! Don’t make the same mistake as Dr. Evil. He had to learn the hard way.