Writing and Graphing One-Step Inequalities
Grade 7 Mathematics Understanding inequality symbols and number line representations 30-minute lesson
What Are Inequalities?
Inequalities show relationships between quantities Use symbols: > (greater than), < (less than), ≥ (greater than or equal to), ≤ (less than or equal to) Unlike equations, inequalities have many possible solutions Example: x > 5 means x can be 6, 7, 8, 100, etc.
Inequality Symbol Practice
Match the symbol to its meaning: > means 'greater than' < means 'less than' ≥ means 'greater than or equal to' ≤ means 'less than or equal to'
Writing Inequalities from Word Problems
Step 1: Identify the unknown quantity (variable) Step 2: Look for key words that indicate inequality Step 3: Choose the correct inequality symbol Step 4: Write the inequality
Let's Try One Together!
Sarah has saved some money. She needs at least $15 to buy a new game. What inequality represents the amount of money Sarah has saved? Let m = money Sarah has saved
Graphing Inequalities on Number Lines
Open circle (○) for < and > (not including the number) Closed circle (●) for ≤ and ≥ (including the number) Shade to the right for 'greater than' Shade to the left for 'less than'
Graph These Inequalities
x > 2 y ≤ -1 z ≥ 4 w < 0
Key Takeaway
'Equations have one solution, but inequalities have infinitely many solutions!'