# Drawing Similar Triangles

## Lesson details

### Key learning points

1. In this lesson, we will learn to draw triangles with the same interior angles using a protractor. We will also discuss the properties of similar triangles.

### Licence

This content is made available by Oak National Academy Limited and its partners and licensed under Oak’s terms & conditions (Collection 1), except where otherwise stated.

## Video

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## Worksheet

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## Starter quiz

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### 5 Questions

Q1.
When constructing a triangle, should you erase the construction lines at the end?
Some of them
Yes
Q2.
Which triangle is impossible to construct?
6cm, 8cm, 3cm
7cm, 3cm, 9cm
All of them
Q3.
What equipment would you use to construct a 9cm, 7cm, 18cm triangle correctly?
Ruler and pencil
Correct answer: Ruler, pencil and compass
Ruler, pencil and protractor
Q4.
Which triangle is impossible to construct?
1cm, 1cm, 1cm
6cm, 2cm, 5cm
Q5.
How do I know from the construction that this is an impossible triangle?
The base is 8cm. 4cm should have been the base.
Correct answer: The circles do not intersect.
The dotted line for 4cm is diagonal

## Exit quiz

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### 5 Questions

Q1.
Complete the sentence: We can draw different triangles that have the same ______ angles using a ruler and a ________.
exterior, compass
exterior, protractor
interior, compass
Q2.
What is the length of the missing side, k, on the larger triangle?
10.4cm
10.8 cm
2.7cm
Q3.
Yasmin and Xiavier are talking about constructing triangles. Yasmin says you need 2 sides lengths to be able to construct a triangle. Xiavier says you need a protractor to construct a triangle. Who is correct?
Both Yasmin and Xiavier
Only Xiavier
Only Yasmin
Q4.
What equipment would you use to construct 95°, 6cm, 55° triangle correctly?
Others
Ruler and pencil
Ruler, pencil and compass
Correct answer: Ruler, pencil and protractor
Q5.
Both angles have the same interior angles of ____, _____ and _______
25°, 25°, 48°