1. Inequalities Ch 3-1 10-12-15

2. Equations Vs. Inequalities An equation is a number sentence that states that two expressions have the same value: X+3 = 7 means: X plus 3 is the same as 7 An inequality is a number sentence that states that one expression is greater than or less than another: X+3  7 means: X plus 3 is greater than 7

3. Equations Vs. Inequalities Equations will always use the equal sign, notice that both sides of the equal sign are equally large: = This makes sense since both sides of an equation are equally large.

4. Equations Vs. Inequalities Inequality signs have different sizes on either side: Which side of this sign is larger? The left or right? > This sign is larger on the left, so the larger value goes on the left.

5. Equations Vs. Inequalities

6. Inequalities…

7. You try, use the correct symbol 7  1 8  10 6  2 4  7 4  8-5 9  1+14 4  -5 4+5  7-6

8. Graphs of inequalities: This is how we visually represent an inequality:

9. My favorite way to graph: The previous slide showed the way most texts and teachers graph, I personally prefer the following: Instead of : We can draw the graph above the number line I think this is easier for you to write and for me to read, but you can use either style.

10. Try this To pass a quality inspection, four random samples of a product must have a total of at least 445 quality points. Write an inequality that models this situation. Q 445 Martin got 103, 112, 115 and 120 for his four samples, write and inequality using these values and state whether Martin passed his inspection.

11. Try this

12. Try some yourself…