How do you use properties of equality to solve equations?

X + 7 = 22

In this lesson you will learn to solve equations… by using

additive inverses

Let’s Review

Properties of numbers

4 = 44 + 2= 4+ 2 4 -3 = 4-3

Let’s Review

When we use the term solution, we mean a value that makes the equation

true x-1=0

1 is our solution

Let’s Review

Additive Inverse

1 + -1 = 0

A Common Mistake

Thinking additive inverses must be negative

Core Lesson

x+5 = 10

x+5 -5 = 10-5

X = 5

+ - 5 is the same as - 5

Core LessonX – 2 = 7

x – 2 + 2= 7+ 2

x = 9

Here we’re looking at -

2 as “a”

In this lesson you have learned how to solve an equation… by

using additive inverses.

Guided Practice

Solve the following equations for x; show your work

x + 3 =13

x – 6 = 20

Extension Activities

Why do we use substitution to check our answers when we solve an equation? Provide an example.

Extension Activities

Define “additive inverse” in your own words. How would you use additive inverses to solve x + 4 = -5 ?

Quick Quiz

Solve for x, show your workx – 7 = 8

Solve for x, show your workx + 2 = 19