Comparing Real Numbers Using Inequalities
Year 9 Mathematics Lesson 2 of 4: Understanding Real Numbers Western Australian Curriculum
Review: What We Learned Last Lesson
The number line helps us visualize and order numbers Numbers to the left are smaller than numbers to the right Real numbers include integers, fractions, and decimals We can place any real number on the number line
WALT: We Are Learning To
Compare real numbers using inequality symbols Use the symbols < (less than) and > (greater than) Use the symbols ≤ (less than or equal to) and ≥ (greater than or equal to) Explain our reasoning using the number line
Success Criteria
I can accurately compare pairs of real numbers I can use inequality symbols correctly (< > ≤ ≥) I can explain my reasoning using the number line I can work with integers, fractions, and decimals
Inequality Symbols: What Do They Mean?
< means 'less than' - the smaller side points to the smaller number > means 'greater than' - the larger side faces the larger number ≤ means 'less than or equal to' ≥ means 'greater than or equal to' Memory trick: The symbol 'eats' the bigger number!
Comparing Numbers on the Number Line
{"left":"On the number line, numbers get larger as we move to the right\nNumbers get smaller as we move to the left\n-5 is to the left of -2, so -5 < -2","right":"3.5 is to the right of 3, so 3.5 > 3\nAny positive number is greater than any negative number\nZero is greater than all negative numbers but less than all positive numbers"}
Hands-On Practice: Number Card Sorting
Work in pairs with number cards and inequality symbols Place numbers on your number line Insert the correct inequality symbol between each pair Explain your reasoning to your partner Challenge: Try comparing fractions and decimals!
Reflection: What Have We Learned?
How do inequality symbols help us compare numbers? What strategies did you use to determine which number was larger? How does the number line support your reasoning? What was challenging about today's lesson?