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4th grade
Course: 4th grade > Unit 11
Lesson 4: Classifying trianglesTypes of triangles review
Review ways to classify triangles based on their sides lengths and angles. Practice classifying triangles.
Classifying triangles by their angles
Acute triangles
An start color #11accd, start text, a, c, u, t, e, end text, end color #11accd triangle has start color #11accd, start text, 3, space, a, n, g, l, e, s, space, t, h, a, t, end text, end color #11accd start color #11accd, start text, e, a, c, h, space, m, e, a, s, u, r, e, space, l, e, s, s, space, t, h, a, n, space, end text, 90, degrees, end color #11accd. Below are examples of start color #11accd, start text, a, c, u, t, e, space, t, r, i, a, n, g, l, e, s, end text, end color #11accd.
Right triangles
A start color #7854ab, start text, r, i, g, h, t, end text, end color #7854ab triangle has start color #7854ab, start text, 1, space, a, n, g, l, e, space, t, h, a, t, space, m, e, a, s, u, r, e, s, space, end text, 90, degrees, end color #7854ab and 2 acute angles. Below are examples of start color #7854ab, start text, r, i, g, h, t, space, t, r, i, a, n, g, l, e, s, end text, end color #7854ab.
Obtuse triangles
An start color #1fab54, start text, o, b, t, u, s, e, end text, end color #1fab54 triangle has start color #1fab54, start text, o, n, e, space, a, n, g, l, e, space, t, h, a, t, space, m, e, a, s, u, r, e, s, end text, end color #1fab54 start color #1fab54, start text, m, o, r, e, space, t, h, a, n, space, end text, 90, degrees, end color #1fab54 and 2 acute angles. Below are examples of start color #1fab54, start text, o, b, t, u, s, e, space, t, r, i, a, n, g, l, e, s, end text, end color #1fab54.
Want to learn more about classifying triangles? Check out this video.
Want to try more problems like this? Check out this exercise
Classifying triangles by their side lengths
Equilateral triangles
An start color #11accd, start text, e, q, u, i, l, a, t, e, r, a, l, end text, end color #11accd triangle has start color #11accd, start text, t, h, r, e, e, space, e, q, u, a, l, space, s, i, d, e, s, end text, end color #11accd. Below are examples of start color #11accd, start text, e, q, u, i, l, a, t, e, r, a, l, end text, end color #11accd triangles.
Isosceles triangles
An start color #7854ab, start text, i, s, o, s, c, e, l, e, s, end text, end color #7854ab triangle has start color #7854ab, start underline, start text, a, t, space, l, e, a, s, t, end text, end underline, end color #7854ab start color #7854ab, start text, t, w, o, space, e, q, u, a, l, space, s, i, d, e, s, end text, end color #7854ab. Below are examples of start color #7854ab, start text, i, s, o, s, c, e, l, e, s, end text, end color #7854ab triangles.
Scalene triangles
A start color #1fab54, start text, s, c, a, l, e, n, e, end text, end color #1fab54 triangle has start color #1fab54, start text, n, o, space, e, q, u, a, l, space, s, i, d, e, s, end text, end color #1fab54. Below are examples of start color #1fab54, start text, s, c, a, l, e, n, e, end text, end color #1fab54 triangles.
Want to try more problems like this? Check out this exercise.
Want to join the conversation?
- Why can't I go back to selecting? I got a wrong and I can't go back(67 votes)
- It just won't let you.(10 votes)
- why is the isosceles triangle and the equilateral both classified as each other(43 votes)
- because an equilateral triangle is all equill sides and an isosceles triangle is two or more equill sides(15 votes)
- Is their any more triangle practices?(21 votes)
- No. You will have to do them over if you want extra practice.(10 votes)
- Why are triangles used in math?(14 votes)
- it is because it uses geometry(5 votes)
- I don’t understand why an equilateral triangle is constantly being defined as and Isosceles triangle.(8 votes)
- An equilateral triangle has 3 equal length sides. An isosceles triangle has at least 2 sides of the same length. Thus all equilateral triangles are also isosceles.(23 votes)
- if all of the angels are acute but lenghths are different what is that?(5 votes)
- um whenever i double tap a question it ameatiatily says its wrong(10 votes)
- dont double tap just tap and check(7 votes)
- i got my one right but it said i got it worng(10 votes)
- it said that a acute was like all the sides lower then 90* but the last one was over 90*(7 votes)
- then it was obtuse(5 votes)
- this was so easy ;-; >:((3 votes)
- ITS NOT IF YOUR ON AN IPAD! Sorry but you must drag the lines together and it’s really frustrating.(13 votes)