Unit 4 Review- Math 7

Unit 4 Review

Prepare for test on Thursday!

4.4: I can solve inequalities

Just like equations.. with ONE main difference:

Flip the sign if you have to multiply or divide both sides by a NEGATIVE number.

Solving inequalities:

• Isolate the variable by:

• Simplifying both sides of the inequality

• Remove constants by undoing addition/subtraction

• Remove coefficients by undoing multiplication/ division <- WATCH OUT ON THIS STEP

• If you are multiplying or dividing by a negative number, FLIP the inequality sign!

Multiple Choice

16 - 4a > 8

• a<-2

• a>-2

• a<2

• a>2

Multiple Choice

22 < 6c + 4

• 11>c

• 3>c

• 11<c

• 3<c

Multiple Choice

-3n + 8 > 29

• n > 7

• n < -7

• n > -7

• n < 7

Multiple Choice

Solve and graph.

-83 < n - 80

• A

• B

• C

• D

Multiple Choice

Solve and graph.

k - 13 > -51

• A

• B

• C

• D

4.5: I can write and solve inequalities for real world situations

Translate words --> Math. Then, SOLVE

Multiple Choice

The dance committee hired a DJ for the fall dance. The DJ charges $125 per hour in addition to $55 for an assistant. The committee wants to keep the total cost under $600. Which inequality represents the maximum amount of hours the DJ will play at the dance?

• 125x + 55 ≤ 600
• 125x + 55 ≥ 600
• 125x + 55 > 600
• 125x + 55 < 600

Multiple Choice

Joan needed $100 to buy a graphing calculator for her math class. Her neighbor will pay her $5 per hour to babysit and her Father gave her $10 for mowing the lawn. Which inequality represents the minimum amount of hours she will need to babysit in order for her to buy her calculator?

• 5x + 10 ≥ 100

• 5x - 100 ≥ 10

• 10x + 5 ≤ 100

• 5x + 10 > 100

4.3: I can write and solve algebraic equations for real world situations

Translate Words--> Math. Then, SOLVE.

It costs $10 to enter the petting zoo. Each cup of food is $2 per animal. Write an equation to represent the cost (c) of feeding (a) animals.

Multiple Choice

Lisa went to the mall to do her back-to-school shopping. When she returned home, she noticed that the number of shirts(s) she purchased was 3 more than twice the number of pants(p) she bought. Write an equation that can be used to represent the number of shirts Lisa purchased

• p = 3 + 2s

• s + 2p = 3

• 2p = s + 3

• s = 3 + 2p

Multiple Choice

Roberto deposits the same amount

of money each month into a checking

account. Use the table to write an

equation to model his balance, B,

after m months.

• B = 200 + 55m

• B = 200 - 55m

• B = 200m + 55

• B = 200m - 55

Multiple Choice

A fitness club opens with 80 members. Each month the membership increases by 15 members. Which equation represents the relationship between the number of months the club has been opened, x, and the total fitness club membership, y?

• y=15x

• y=15x+80

• y=x+15

• y=80x+15

Multiple Choice

A cell phone company charges $3.00 to make a phone call plus $0.15 for each minute for each minute you talk. Which equation would you use to determine the total cost, c, of a phone call that is m number of minutes long?

• c = 3.00 - 0.15m
• c = 0.15 + 3.00m
• 3.00 = c + 0.15
• c = 3.00 + 0.15m

4.2: I can solve algebraic equations

Isolate the variable by performing opposite operations!

Solving Equations

1. Simplify

2. Remove constants

3. Remove coefficients

Fill in the Blanks

Solving Equations

1. Simplify

2. Remove constants

3. Remove coefficients

Solving Equations

1. Simplify

2. Remove constants

3. Remove coefficients

Solving Equations

1. Simplify

2. Remove constants

3. Remove coefficients

Solving Equations

1. Simplify

2. Remove constants

3. Remove coefficients

4.1: I can identify equivalent equations

Equivalent equations have the same solution!

Equivalent Equations

Creating equivalent equations

Equivalent Equations

Creating equivalent equations

Poll

Are these equations equivalent?

 $10x+10=50$  

and
 $6x+4=28$  

• Yes

• No

Equivalent Equations

Creating equivalent equations

Open Ended

 $-p+15=14$  and  $12-2p=2$  Are these equations equivalent? Why or why not? 

Multiple Choice

Which equation is equivalent to this equation:

 $4x-1=11$  

•  $x=12$  

•  $4x-1=15$  

•  $x+10=13$  

•  $8-x=11$  

Multiple Choice

Which equation is NOT equivalent to the equation:

 $-9\left(2-x\right)+10=1$  

•  $18-9x+10=1$  

•  $9x-8=1$  

•  $-18+9x+10=1$  

•  $9x=9$  

•  $x=1$