7th Grade Math

the Results

1. What does the bar labeled x represent?


2. What is the value of x?


3. If x represents the possible weight of Mia’s shoes, could there be
   more than one value of x? If so, give an example.


4. Refer to Step 3. Write an inequality to represent the situation.


5. Refer to the bar diagram in Activity 1. Explain why the bar
   diagram is considered an inequality.

You can also use a balance to model and solve inequalities.

Model x + 2 < 5.

On one side of a

balance place a paper

bag and 2 cubes.

On the other side of

the balance place

5 cubes.

The side with the bag and 2 blocks weighs less than the side with

5 blocks.

The model shows the inequality x + 2 < 5.

the Results

6. Assume the paper bag is weightless. How many blocks would be in
   the bag if the left side balanced the right side?


7. Refer to Exercise 6. Explain how you determined your answer.


8. What numbers of blocks can be in the bag so that the left side weighs less
   than the right side? Write an inequality to represent your answer.


9. Refer to the model in Activity 2. Explain why the blocks and the bag on the
   balance is considered an inequality.


10. E WRITE MATH Compare and contrast the solution of an equation and an
    inequality. Include an example in your explanation.

Lesson 4A Inequalities 243

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