Solving Inequalities with Addition and Subtraction

Download Report

Transcript Solving Inequalities with Addition and Subtraction

6.1 Solving Inequalities with
adding and subtracting
1. graph inequalities on a number line.
2. solve inequalities using addition and
subtraction.
SOL: A.1, A.3
Designed by Skip Tyler, Varina High School
Edited by Eddie Judd, Crestwood Middle School
1) Graph the solution set of
x < 3.
o
-5
0
5
When you have < or >, use an open dot!
2) Graph the solution set of
y ≥ -5/4.
-5
•
0
5
When you have ≤ or ≥, use a closed dot!
Converting -5/4 to a decimal = -1.25
3) Graph the solution set of
p ≠ 2.
-5
0
o
5
When you have ≠, use an open dot and shade
both ways!
4) Which inequality would have a
closed dot on the number line?
1.
2.
3.
4.
>
<
≥
≠
Answer Now
5) Which inequality does NOT use an
open dot on the number line?
1.
2.
3.
4.
≤
<
>
≠
Answer Now
6) Solve x + (-14) < 16
x - 14 < 16
+ 14 + 14
{x|x < 30}
Solve this problem like an
equation
1. Draw “the river”
2. Eliminate double signs
3. Add 14 to both sides
4. Simplify Set Notation
5. Check your limit
6. Graph the solution
29
30 + (-14) = 16
16 = 16
o
30
31
1.
2.
7) Solve y + 21 ≥ 7
- 21 -21
Draw the “river”
Subtract 21 from
{y|y
≥
-14}
both sides
3. Simplify in
Set Notation
4. Check your limit
5. Graph the solution
-15
(-14) + 21 = 7
7=7
●
-14
-13
8) Solve
1.
2.
3.
4.
5.
6.
7.
8.
Draw “the river”
Subtract 8y from both
sides
Simplify
Add 14 to both sides
Simplify
Rewrite inequality in
Set Notation
Check your limit
Graph the solution
16
8y + 3 > 9y - 14
- 8y
- 8y
3 > y - 14
+ 14 + 14
17 > y
{y|y < 17}
8(17) + 3 = 9(17) - 14
o
17
18
9) What is the graph of 7 ≤ m?
1.
2.
3.
4.
6
6
6
6
o
7
o
7
●
7
●
7
Answer Now
8
8
8
8
10) Solve
1.
2.
3.
4.
5.
6.
7.
Draw “the river”
Subtract 2r from both
sides
Simplify
Add 17 to both sides
Simplify in
Set Notation
Check your limit
Graph the solution
30
3r - 17 ≥ 2r + 14
- 2r
- 2r
r – 17 ≥ 14
+ 17 + 17
{r|r ≥ 31}
3(31) - 17 = 2(31) + 14
●
31
32
11) Solve -2x + 6 ≥ 3x - 4
1.
2.
3.
4.
{x|x ≥
{x|x ≤
{x|x ≥
{x|x ≤
-2}
-2}
2}
2}
Answer Now
12) Joanna’s tests were 87, 93, 88
and 94. What must her 5th grade be
to get a total of at least 459?
1.
2.
3.
4.
96
97
98
100
Answer Now