Using Inequalities to Solve Real World Problems

Solve inequalities by Substitution

I can...

• Classify inequalities as true or false.

• Using substitution of a given number from a specified set, determine if an inequality is true or false.

Standards

• 6.AF.4

  Understand that solving an equation or inequality is the process of answering the following question: Which values from a specified set, if any, make the equation or inequality true? Use substitution to determine whether a given number in a specified set makes an equation or inequality true.

• 6.AF.6

  Write an inequality of the form x > c, x ≥ c, x < c, or x ≤ c, where c is a rational number, to represent a constraint or condition in a real-world or other mathematical problem. Recognize inequalities have infinitely many solutions and represent solutions on a number line diagram.

Multiple Choice

REVIEW - 6x + 7y - 5 when x=2 and y = 3

• 12

• 28

• 72

• 108

True or False

-6 > -3

Prove it.

Vocabulary and symbols

• Inequality - a math sentence that shows two values are no equal

• > Greater than

•  $\ge$  Greater than or equal to

• < Less than

•  $\le$  Less than or equal to

• = equal  $\ne$  not equal (or inequal)

True or False

 $7\le7$  

Multiple Choice

True or Flase

$$-4\le-3$$  

• True

• False

Multiple Choice

True or False n+6 < 14 if n=8

• True

• False

Multiple Choice

True or False

$$3b+2\le14\ if\ b=4$$  

• True

• False

Multiple Choice

Use the replacement set to find the solution set to the inequality

$$c+5\ \le16;\ \left\{10,\ 11,\ 12\right\}$$  

• {10}

• {10, 11} 

• {10, 11, 12}

Multiple Select

What are four symbols that can be used to represent an inequality?

• $$=$$

• $$>$$

• $$<$$

• $$\le$$

• $$\ge$$

Open Ended

Why can an algebraic expression have more than one solution, but a numerical expression cannot?

Poll

How are you feeling about inequalities?

• I'm a boss at it

• I could pass.

• What is this all about?!