Lesson 5: Graph Inequalities6.AT.9

I can…

I can graph the solutions of an inequality on a number line.

Key words

• Number line — A straight line where numbers are placed in order; numbers get smaller to the left and larger to the right.
• Open circle — An empty circle showing a number is NOT included.
• Closed circle — A filled-in circle showing a number IS included.
• Solution set — All the numbers that make the inequality true.
• Inequality — A math sentence comparing two amounts with <, >, ≤, or ≥.
• Boundary point — The number on the number line where the solution set starts.

Steps

1. Graph t ≥ 2. The boundary number is 2.
2. The symbol ≥ includes 2, so I draw a closed (filled) circle at 2.
3. 'Greater than or equal to' means larger values work, so I shade to the right.
4. Now the graph shows 2, 3, 4, and every value above 2.

Try it

How would you graph the inequality x ≥ 9?

Check your answer

Closed circle at 9, shaded right

x ≥ 9 means 9 is included (closed circle) and values are 9 or greater (shaded right).

Sentence starter

I know ___ because ___.

Goal: I can explain my graph using the words number line, open circle, closed circle, and solution set.