Download 7-2 Solving Inequalities Using Multiplication and Division

Warm ups
Solve for x.
1.
2.
3.
4.
5.
6.
3 + x < 12
23 > x – 15
2x – 10 > x + 6
-3.4 > 0.9 – p
-3 + x > 2x – 4
2.
3
x  3  15
1. x < 9
2. x < 38
3. x > 16
4. p > 4.3
5. x < 1
6. x = 27
7-2 Solving Inequalities
Using Multiplication and
Division
Objective: To solve inequalities
by multiplying and dividing.
Standard 5.0
Flip Inequality sign when:
1.
2.
You need to move the letter (variable) to the left
3<x
-5 > p
x 3
p  5
You multiply or divide by a negative number
1
 x4
3
x  12
-2x > 4
x  2
Examples – solve and graph
1.
2.
3w > 27
3
3
w>9
(12)
(12)
x<3
12 2
x < 18
6
Examples – solve and graph
-4x < -3
-4
-4
x > 3/4
3.
4.
-4
3
Divide by a negative – FLIP!
6
18 < -3m -4
3
4
-24 > m Multiply by a negative – FLIP!
m < -24 Move letter to left – FLIP!
TOO – watch the flip!
6  4x
6 y  24
4
x  24
5
x
 5
4
3m
18  
4
Multi-step inequalities
8.
3n + 4 > -14
-4
-4
3n > -18
3
3
n>-6
Homework

Pg. 396 # 21-43 ODD
7-1 – 7-2 Review
Math Lab.
Standard 5.0
Flip Inequality sign when:
1.
2.
You need to move the letter (variable) to the left
3<x
-5 > p
x 3
p  5
You multiply or divide by a negative number
1
 x4
3
x  12
-2x > 4
x  2
7-1 Review
x 5  9
x 15  6
3 x2
7-2 Review
x
 10
2
6 x  18
5
3 x
2
7-3 Preview/Review
2m  7  17
7x 1  26  2x
2  3x  2
7-3 Preview/Review
2x  5  3x  7
2x  3
7
5
4 y  2  8 y  (6 y  10)