7th Grade Math

Addition and Subtraction Equations

PART A BCD

Multi-Part

Lesson 1

Get ConnectED

GLE 0706.3.8

Use a variety of strategies

to efficiently solve linear

equations and inequalities.

SPI 0706.3.7 Translate

between verbal and

symbolic representations of

real-world phenomena

involving linear equations.

Also addresses GLE 0706.1.4,

GLE 0706.1.8, GLE 0706.3.7.

208 Equations and Inequalities

Solve One-Step Addition

and Subtraction Equations

VIDEO GAMES Max had some video games, and then he bought

two more games. Now he has six games.

Y

1

1

1

1

1

1

1

1

= Now he has six games.

He bought two more.

He started with an

unknown number

of games.

1. What does x represent in the figure?


2. What addition equation is shown in the figure?


3. How many games did Max have in the beginning?

An equation is a sentence stating that two quantities are equal. You

can solve the equation x + 2 = 6 by subtracting 2 from each side of

the equation.

Y

1

1

1

1

1

1

1

= 1

x + 2 = 6

• 2 = - 2
  x = 4

The equations x + 2 = 6 and x = 4 are equivalent equations because

they have the same solution, 4.

twom

Main Idea

Solve addition and

subtraction equations.

Vocabulary

equation

equivalent equations

Subtraction Property of Equality

Words If you subtract the same number from each side of an

equation, the two sides remain equal.

Symbols If a = b, then a - c = b - c.

Examples Numbers Algebra

6 = 6 x + 2 = 6

• 2 = - 2 - 2 = - 2
  4 = 4 x = 4

V

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