UNIT 2

REVIE

W

CUSTOMARY LENGTH

12 inches (in) = 1 foot (ft)

36 inches = 3 feet or 1 yard (yd)

5,280 feet = 1 mile (mi)

To change from a larger unit of

measure to a smaller unit, MULTIPLY.

To change from a smaller unit of

measure to a larger unit, DIVIDE.

Copy this in your

booklet page 12

Length

American standard

1 mile = 1760 yards = (5280 feet)1 yard = 3 feet1 foot = 12 inches1 mil = 1/1,000 inch

Metric standard

1 kilometer = 1000 meters1 meter = 10 decimeters1 decimeter = 10 centimeters( 1 meter = 100 centimeters)1 centimeter = 10 millimeters

Conversion:1 inch is defined to be exactly 2.54 cm in July, 1959.

(before this, the UK inch measures 2.53998 cm, while the US inch was 2.540005 cm)

Length

American standard

1 mile = 1760 yards = (5280 feet)1 yard = 3 feet1 foot = 12 inches1 mil = 1/1,000 inch

Metric standard

1 kilometer = 1000 meters1 meter = 10 decimeters1 decimeter = 10 centimeters( 1 meter = 100 centimeters)1 centimeter = 10 millimeters

Conversion:1 inch is defined to be exactly 2.54 cm in July, 1959.

(before this, the UK inch measures 2.53998 cm, while the US inch was 2.540005 cm)

Length

American standard

1 mile = 1760 yards = (5280 feet)1 yard = 3 feet1 foot = 12 inches1 mil = 1/1,000 inch

Metric standard

1 kilometer = 1000 meters1 meter = 10 decimeters1 decimeter = 10 centimeters( 1 meter = 100 centimeters)1 centimeter = 10 millimeters

Conversion:1 inch is defined to be exactly 2.54 cm in July, 1959.

(before this, the UK inch measures 2.53998 cm, while the US inch was 2.540005 cm)

Length

American standard

1 mile = 1760 yards = (5280 feet)1 yard = 3 feet1 foot = 12 inches1 mil = 1/1,000 inch

Metric standard

1 kilometer = 1000 meters1 meter = 10 decimeters1 decimeter = 10 centimeters( 1 meter = 100 centimeters)1 centimeter = 10 millimeters

Conversion:1 inch is defined to be exactly 2.54 cm in July, 1959.

(before this, the UK inch measures 2.53998 cm, while the US inch was 2.540005 cm)

The distance around the

outside of a shape is called the perimeter.

8 cm

6 cm

8 cm

6 cm

The perimeter of the shape is 8 + 6 + 8 + 6 = 28cm.

First we need to find he length of each side by counting the squares.

Now find the perimeter of these shapes. They are

not drawn to scale.

3cm

3cm

3cm

3cm

3cm

3cm

5cm

7cm7cm

3cm

4cm 4cm

4cm 4cm

3cm 3cm

3cm3cm

Perimeter = 18cm Perimeter = 22cm Perimeter = 28cm

Take a walk around the edge!Take a walk around the edge!

The perimeter is…The perimeter is…

32 cm !32 cm !

This is a regular octagon with sides 4 cm

This is a regular octagon with sides 4 cm

2828

- 16 -16

r = -23

-23 + 16 = -7

1) SOLVE R + 16 = -7

1. Draw “the river” to separate the equation into 2 sides

2. Subtract 16 from both sides

3. Simplify vertically

4. Check your answer by substituting your answer back into the problem

2) SOLVE X + 2 = -3GET THE VARIABLE BY ITSELF. WHAT IS YOUR FIRST STEP?

1. Add 2 to both sides

2. Subtract 2 from both sides

3. Add 3 to both sides

4. Subtract 3 from both sides

Answer Now

3) SOLVE 8 = M - 3

1.m = 52.m = 113.m = 244.m = 8/3

Answer Now

APPLICATION

Clare had 9 bears. After she gave away some bears to her brother, Clare still had 3 bears. How many bears did Clare give away?

9 – ? = 3

Clare had some bears. After she gave away 3 bears to her cousin, she had 6 bears left. How many bears did Clare have to begin with?

? – 3 = 6

NEGATIVE NUMBERS - THIS TIME THE SCALE IS HORIZONTAL

0 1 2 3 4 5 6-1-2-3-4-5-6

CAN YOU ORDER THIS SET OF NUMBERS STARTING WITH THE COLDEST?

20

5

- 2

- 15 10

- 20

-5 50 10-10

A number line has many functions. Previously, we learned that numbers to the right of zero are positive and numbers to the left of zero are negative. By putting points on the number line, we can graph values.

If one were to start at zero and move seven places to the right, this would represent a value of positive seven. If one were to start at zero and move seven places to the left, this would represent a value of negative seven.

+7-7

-5 50 10-10

+7-7

Both of these numbers, positive seven (+7) and negative seven (-7), represent a point that is seven units away from the origin.

The absolute value of a number is the distance between that number and zero on a number line. Absolute value is shown by placing two vertical bars around the number as follows:

5 The absolute value of five is five.

-3 The absolute value of negative three is three.

LET’S PRACTICE

1. -1

2. 5

3. 6

4. -19

5. -179

6. 57

EXAMPLE 2: (-2 ) + 51. Our car starts from 0 facing

right.2. It then backs up 2 units (to the

left) because it sees the - sign.

EXAMPLE 3: 5 – 31. Our car still starts at 0 facing

right.2. It then moves forward 5 units.

EXAMPLES OF ADDITION

Four more than eleven

4+11

14 increased by 2

14 + 2

The sum of 9 , 4, and 11

9 + 4 + 11

EXAMPLES OF SUBTRACTION

34 decreased by 11

34 -11

17 less than 30

30 - 17

27 take away 10

27 - 10

EXAMPLES OF EQUALS

The sum of 4 and 19 is 23

4 + 19 = 23

The difference of 14 and 5 is 9

14 - 5 = 9

15 less than 6 becomes 9

15 – 6 = 9

EXAMPLES OF EQUALS

The sum of 4 and 19 is 23

4 + 19 = 23

The difference of 14 and 5 is 914 - 5 = 9

15 less than 6 becomes 915 – 6 = 9

UNIT 2 REVIEW

Review Questions on page 84 and 85 #1-40