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.


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5 Questions

When constructing a triangle, should you erase the construction lines at the end?
Correct answer: No
Some of them
Which triangle is impossible to construct?
Correct answer: 5cm, 2cm, 3cm
6cm, 8cm, 3cm
7cm, 3cm, 9cm
All of them
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
Which triangle is impossible to construct?
1cm, 1cm, 1cm
6cm, 2cm, 5cm
Correct answer: 8cm, 2cm, 6cm
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

5 Questions

Complete the sentence: We can draw different triangles that have the same ______ angles using a ruler and a ________.
exterior, compass
exterior, protractor
interior, compass
Correct answer: interior, protractor
What is the length of the missing side, k, on the larger triangle?
10.8 cm
Correct answer: Not enough information
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
Correct answer: Neither is correct
Only Xiavier
Only Yasmin
What equipment would you use to construct 95°, 6cm, 55° triangle correctly?
Ruler and pencil
Ruler, pencil and compass
Correct answer: Ruler, pencil and protractor
Both angles have the same interior angles of ____, _____ and _______
25°, 25°, 48°
Correct answer: 48°, 25°, 107°
48°, 25°, 73°
48°, 48°, 25°,

Lesson appears in

UnitMaths / Constructing triangles and quadrilaterals