Switch to our new maths teaching resources

Slide decks, worksheets, quizzes and lesson planning guidance designed for your classroom.

Play new resources video

Lesson details

Key learning points

  1. In this lesson, we will understand that the interior angles in a triangle sum to 180°. We will also solve problems involving unknown angles in 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.

Loading...

6 Questions

Q1.
What is a triangle with at least two equal sides called?
Equilateral triangle
Correct answer: Isosceles triangle
Obtuse triangle
Scalene triangle
Q2.
What is a triangle with three equal sides called?
Correct answer: Equilateral triangle
Isosceles triangle
None
Scalene triangle
Q3.
Would it be possible to draw a scalene triangle with more than one obtuse angle?
Correct answer: No, this will be impossible
Yes, this will be possible
Q4.
The sum of all the angles of a triangle is:
100 degrees
Correct answer: 180 degrees
360 degrees
90 degrees
Q5.
Zaki and Connor are looking at the diagram on the right. Who do you agree with? Why?
An image in a quiz
Connor
Neither of them
Correct answer: Zaki
Q6.
I am thinking of a triangle which have the following properties: no lines of symmetry and has one right angle. Which triangle am I thinking of?
Equilateral triangle
Isosceles triangle
Correct answer: Scalene triangle

6 Questions

Q1.
Grace has measured the three angles in a triangle. Two of her measurements are 48° and 70°. What is the third measurement?
118°
152°
242°
Correct answer: 62°
Q2.
Find the size of the missing angle
An image in a quiz
157
23°
Correct answer: 78.5°
Q3.
Find the missing angle labelled, x
An image in a quiz
106°
127°
Correct answer: 53°
90°
Q4.
Find the missing angle, labelled x
An image in a quiz
Correct answer: 112°
145°
34°
68°
Q5.
Work out the missing angle, labelled x
An image in a quiz
11°
169°
Correct answer: 49°
60°
Q6.
The ratio of three angles in a triangle are 1:2:3. Work out the size of each angle.
10°: 20°: 30°
Correct answer: 30°:60°:90°
60°:60°:60°
90°:45°:45°