Year 5

Comparing & classifying isosceles and scalene triangles

Year 5

Comparing & classifying isosceles and scalene triangles

Lesson details

Key learning points

  1. In this lesson, we will compare different triangles and introduce isosceles and scalene triangles.


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6 Questions

Which properties do all triangles have?
2 sides and 3 vertices
3 sides and 2 vertices
Correct answer: 3 sides and 3 vertices
4 sides and 4 vertices
What is the name given to a regular triangle?
Correct answer: Equilateral triangle
Right angled triangle
Which of the statements best describe an equilateral triangle?
1 angle equal to 90 degrees
2 angles equal to 180 degrees
Correct answer: 3 angles, where each angle is equal to 60 degrees
3 sides with different measurements
Which statement best describes a right angled triangle
Correct answer: 1 angle that measures to 90 degrees
3 angles that measure exactly the same
A triangle with a width of 10cm
A triangle with three 60 degree angles
It is possible to create a large equilateral triangle from either...
2 or 4 smaller equilateral triangles
3 or 5 smaller equilateral triangles
Correct answer: 4 or 9 smaller equilateral triangles
6 or 9 smaller equilateral triangles
If a triangle has the angles: 60 degrees and 30 degrees, what is the 3rd angle?
180 degrees
30 degrees
60 degrees
Correct answer: 90 degrees

5 Questions

What is the name given to a triangle with 3 equal sides?
Correct answer: Equilateral triangle
Right angled triangle
Scalene triangle
What is the name given to a triangle which has the following three angles: 80°, 40° and 60° ?
Equilateral triangle
Isosceles triangle
Right angled triangle
Correct answer: Scalene triangle
If a triangle has the angles of 90° and 60°, what is the third angle?
Correct answer: 30°
Which of these are NOT interior angles of a triangle?
Correct answer: 40°, 55° and 75°
60°, 60° and 60°
70° , 70° and 40°
Correct answer: 80°, 20° and 70°
A right angled triangle can also be ...
a scalene or an equilateral triangle
Correct answer: a scalene or isosceles triangle
an equilateral triangle
an isosceles or an equilateral triangle