# 8.2: Solve for Unknowns

Look at the equation below. Can you figure out the value of ? In this concept, we will practice using the order of operations and the distributive property to solve equations.

### Guidance

The **order of operations** tells us the correct order of evaluating math expressions. We always do ** parentheses first**. Then we do

**. Next we do**

*exponents***and finally**

*multiplication and division (from left to right)***. The**

*addition and subtraction (from left to right)***allows us to remove parentheses when there is an unknown inside of them.**

*distributive property*In order to evaluate expressions using the distributive property and the order of operations, we can use the problem solving steps to help.

- First,
**describe**what you see in the problem. What operations are there? - Second, identify what
**your job**is. In these problems, your job will be to solve for the unknown. - Third, make a
**plan**. In these problems, your plan should be to use the distributive property and the order of operations. - Fourth,
**solve**. - Fifth,
**check**. Substitute your answer into the equation and make sure it works.

#### Example A

Solve for the unknown. Follow the order of operations and show each step.

**Solution:**

We can use the problem solving steps to help us with the order of operations.

#### Example B

Solve for the unknown. Follow the order of operations and show each step.

**Solution:**

We can use the problem solving steps to help us with the order of operations.

#### Example C

Solve for the unknown. Follow the order of operations and show each step.

**Solution:**

We can use the problem solving steps to help us with the order of operations.

#### Concept Problem Revisited

We can use the problem solving steps to help us with the order of operations.

### Vocabulary

The ** order of operations** tells us the correct order of evaluating math expressions. We always do

**. Then we do**

*parentheses first***. Next we do**

*exponents***and finally**

*multiplication and division (from left to right)***. The**

*addition and subtraction (from left to right)***allows us to remove parentheses when there is an unknown inside of them.**

*distributive property*### Guided Practice

For each problem, solve for the unknown. Follow the order of operations and show each step.

1.

2.

3.

**Answers:**

1. Here are the steps to solve:

2. Here are the steps to solve:

3. Here are the steps to solve:

### Practice

For each problem, solve for the unknown. Follow the order of operations and show each step.

### Image Attributions

## Description

## Learning Objectives

Students apply the distributive property and use the order of operations to find the values of unknowns. Students use problem solving steps to help.