Angles

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Angles
Level E
Revising Basic Angles
Naming Angles
Calculating Missing angles
Angles in a Triangle
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Corresponding Angles
Alternate Angles
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Starter Questions
Level E
Q1. Convert to the 24 hour clock.
(b) 650 am
(a) 725 pm
Q2. Write down the type of angle that is less
than 90 deg.
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Q3. Calculate 2.34 4.7 0.12
Q4. Round the following to nearest 1000.
(a) 12,501
(b) 369,765
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Type of Angles
Level E
Learning Intention
Success Criteria

1. To be able to identify acute, right-angle,
   obtuse, straight line and reflex angles.

1. To revise Type of Angles from level D.

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Type of Angles
Level E
Acute less than 90o
Obtuse Between 90o 180o
Right - Angle exactly 90o
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Straight Line Angle exactly 180o
reflex over 180o less than 360o
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Type of Angles
Level E
Now try Ch12 (page 146) Exercise 1
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Starter Questions
Level E
Q1. Convert to the 12 hour clock.
(b) 0540
(a) 1715
Q2. Write down 2 numbers that add to give 8
and multiply to give 15.
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Q3. Calculate 5.65 1.3
Q4. Round the following to nearest 100.
(a) 13,551
(b) 369,449
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Naming Angles
Level E
Learning Intention
Success Criteria

1. To be able to name an angle.

1. To explain how we name angles by THREE capital
   letters with the angle sign. The middle letter
   being where the angle is.

1. Understand the difference between the type of
   angle and the name of an angle.

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Naming Angles
Level E
A
X
Y
B
C
Z
Type of angle is acute
Type of angle is obtuse
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Name of angle is ? ABC
Name of angle is ? ZYX
MIDDLE LETTER IS ALWAYS WHERE THE ANGLE IS
ALWAYS 3 CAPITAL LETTERS
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Naming Angles
Level E
Now try Ch12 (page 147) Exercise 2
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Starter Questions
Level E
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Find Missing Angles
Level E
Learning Intention
Success Criteria

1. To know 360o in a circle.

1. To calculate missing angle give all other angles.

1. Find missing angle given all other angles.

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Find Missing Angle
Level E
55o
115o
Two angles making a straight line add to
180o (Supplementary angles)
Two angles making a right angle add to
90o (Complementary angles)
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146o
145o
146o
Angles round a point always add up to 360o
angles opposite each other at a cross are equal.
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Find Missing Angle
Level E
Now try Ch12 (page 149) Exercise 3
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Level E Starter Questions
Level E
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Sum of Angles in a Triangle
Level E
Learning Intention
Success Criteria

1. To know all angles in a triangle add to 180o.

• To show that all the angles
• in a triangle sum to 180o.

1. Use knowledge to solve problems.

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To determine the angle sum of any Triangle
Level E
Cut off corners ?
Cut off corners ?
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Cut off corners ?
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angle sum of any Triangle
Level E
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180o
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Sum of Angles in a Triangle
Level E
Copy out the following triangles and find the
missing angles.
xo
87o
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xo
32o
xo
xo
Remember all the angles add up to 180o
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Sum of Angles in a Triangle
Level E
Now try Ch12 (page 151) Exercise 4 starter at Q3
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Starter Questions
Level E
Q1. Solve the equation below
Q2. Find two numbers that multiply add to give
18 and subtract to give 3.
Q3. Find the average and range of the numbers
below
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2,8,8,10
Q4. Find
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Angles
Corresponding Angles
Level E
Learning Intention
Success Criteria

1. To understand the term corresponding angles.

1. To explain the term corresponding angles
and show how we use the property to solve
problems.
2. To be able to use property to solve problems.
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Angles
Corresponding Angles
Level E
Which angles are equal?
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Angles
Corresponding Angles
Level E
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Which angles are equal?
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Angles
Corresponding Angles
Level E
Which angles are equal to the shaded angle?
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Angles
Level E
Which angles are equal to the shaded angle?
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Angles
Corresponding Angles
Level E
look for
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shapes
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Angles
Corresponding Angles
Level E
What is the value of letter x?
120
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x
120
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Angles
Corresponding Angles
Level E
100
What is the value of letter a?
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a
100
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Angles
Corresponding Angles
Level E
b
48
48
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What is the value of letter b?
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Angles
Corresponding Angles
Level E
What is the value of letter c?
110
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c
110
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Angles
Corresponding Angles
Level E
70
What are the values of letters a and b?
b
110
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a
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Angles
Corresponding Angles
Level E
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What are the values of the missing angles?
115
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Angles
Corresponding Angles
123
Level E
57
What are the values of the missing angles?
123
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Angles
Level E
Corresponding Angles
Now try Exercise 5 Ch12 (page 154)
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Starter Questions
Level E
Q1. Solve the equation below
Q2. Find two numbers that multiply to give
48 and divide to give 3.
119o
Q3. Find missing angles
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bo
ao
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Angles
Alternate Angles
Level E
Learning Intention
Success Criteria

1. To understand the term alternate angles.

1. To explain the term alternate angles and
show how we use the property to solve problems.
2. To be able to use property to solve problems.
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Angles
Alternate Angles
Level E
Look for
- Z shapes
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equal angles
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Angles
Alternate Angles
Level E
Find the value of a ?
35
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a
35
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Angles
Alternate Angles
Level E
b
43
Find the value of b ?
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43
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Angles
Alternate Angles
Level E
Find the value of c ?
33
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33
c
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Angles
Alternate Angles
Level E
123
Find the value of d ?
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d
123
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Angles
Alternate Angles
Level E
50
Find the value a and b ?
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a
b
130
50
43
Angles
Alternate Angles
Level E
135
Find the value of a and b ?
c
45
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d
45
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Angles
Alternate Angles
60
c
120
Find the value a, b and c ?
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b
60
120
a
45
Angles
Level E
Alternate Angles
Now try Exercise 6 Ch12 (page 157)
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