Year 8
Year 8

Interior angles in a triangle

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Lesson details

Key learning points

  1. In this lesson, we will learn about the interior angles in a triangle, and how to find unknown angles in various types of triangles.


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5 Questions

The total sum of the interior angles in a triangle is...
Correct answer: 180 degrees
360 degrees
45 degrees
90 degrees
A right angled triangle with one angle as 23 degrees would mean the remaining interior angle would be...
157 degrees
180 degrees
Correct answer: 67 degrees
77 degrees
In an equilateral triangle, each interior angle would be equal to...
180 degrees
3 degrees
Correct answer: 60 degrees
90 degrees
If a base angle of an isosceles triangle was 34 degrees, what would the other base angle be?
146 degrees
Correct answer: 34 degrees
56 degrees
66 degrees
If the base angles of an isosceles triangle were 34 degrees, what would the unknown angle be?
Correct answer: 112