7th Grade Math

Inequalities

PART A BCDE

4

Multi-Part

Lesson

Get ConnectED

GLE 0706.3.8

Use a variety of strategies

to efficiently solve linear

equations and inequalities.

SPI 0706.3.9 Solve linear

inequalities in one variable

with rational coefficients

symbolically or graphically.

Also addresses GLE 0706.1.8.

242 Equations and Inequalities

Solve Inequalities

LUGGAGE Airlines charge a fee for checked luggage that weighs

greater than 50 pounds. Mia’s suitcase currently weighs 35 pounds

and she still needs to pack her shoes. What is the maximum amount

her shoes can weigh so Mia will not be charged a fee?

An inequality is a mathematical sentence that compares quantities.

Words Symbols

x is less than two x < 2

x is greater than or equal to four x ≥ 4

To solve an inequality means to find values for the variable that make

the sentence true. You can use bar diagrams to solve inequalities.

What do you need to find? the maximum amount the shoes can

weigh so Mia is not charged a fee

Draw a bar above a number line that represents the

maximum luggage weight.

0 5101520 25 3035 40 4550 55

Pounds

Luggage maximum weight

Draw a bar above that bar for Mia’s luggage.

0 51015 20 2530 35 4045 5055

Mia’s luggage weight

Pounds

Luggage maximum weight

Draw a bar connected to the bar that represents the

weight of Mia’s luggage. Label this bar x.

0 5101520 25 3035 4045 50 55

Mia’s luggage weight x

Pounds

Luggage maximum weight

Main Idea

Use models to solve

problems involving

inequalities.

Vocabulary

inequality

V

i

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