# Lesson 13

Reintroducing Inequalities

### Problem 1

For each inequality, find two values for $$x$$ that make the inequality true and two values that make it false.

1. $$x+3>70$$
2. $$x+3<70$$
3. $$\text-5x<2$$
4. $$5x<2$$

### Problem 2

Here is an inequality: $$\text-3x > 18$$.

1. List some values for $$x$$ that would make this inequality true.
2. How are the solutions to the inequality $$\text-3x \geq 18$$ different from the solutions to $$\text-3x > 18$$? Explain your reasoning.

### Problem 3

Here are the prices for cheese pizza at a certain pizzeria:

pizza size price in dollars
small 11.60
medium
large 16.25
1. You had a coupon that made the price of a large pizza $13.00. For what percent off was the coupon? 2. Your friend purchased a medium pizza for$10.31 with a 30% off coupon. What is the price of a medium pizza without a coupon?

3. Your friend has a 15% off coupon and $10. What is the largest pizza that your friend can afford, and how much money will be left over after the purchase? ### Solution Teachers with a valid work email address can click here to register or sign in for free access to Formatted Solution. (From Unit 4, Lesson 12.) ### Problem 4 Select all the stories that can be represented by the diagram. A: Andre studies 7 hours this week for end-of-year exams. He spends 1 hour on English and an equal number of hours each on math, science, and history. B: Lin spends$3 on 7 markers and a $1 pen. C: Diego spends$1 on 7 stickers and 3 marbles.

D:

Noah shares 7 grapes with 3 friends. He eats 1 and gives each friend the same number of grapes.

E:

Elena spends $7 on 3 notebooks and a$1 pen.