# Classify Triangles Worksheets

### Classify Triangles Worksheets

In these free math worksheets, students analyze and classify triangles based on side length, angle measure, or both.

How to classify triangles?
Triangles can be classified based on the length of their sides and the size of their angles.
Here are the common classifications:

Based on the length of the sides:

• Scalene triangle: A triangle with no equal sides.
• Isosceles triangle: A triangle with two equal sides.
• Equilateral triangle: A triangle with three equal sides.

Based on the size of the angles:

• Acute triangle: A triangle with all three angles less than 90 degrees.
• Right triangle: A triangle with one angle equal to 90 degrees.
• Obtuse triangle: A triangle with one angle greater than 90 degrees.

Combining the two classifications, we can have more specific classifications such as:

• Right isosceles triangle: A triangle with one angle equal to 90 degrees and two equal sides.
• Obtuse scalene triangle: A triangle with one angle greater than 90 degrees and no equal sides.
• Acute equilateral triangle: A triangle with all three angles less than 90 degrees and three equal sides.

Have a look at this video if you need to review how to classify by sides and angles.

Click on the following worksheet to get a printable pdf document.
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### More Classify Triangles Worksheets

Printable
Classify Triangles Worksheet #1
Classify Triangles Worksheet #2

Analyze Triangles Word Problems

1. A triangle cannot have one obtuse angle and one right angle. True or False?
2. An equilateral triangle is isosceles. True or False?
3. Every triangle has at least ____ acute angles.
4. A triangle cannot have both an acute angle and a right angle. True or False?
5. A right triangle is always scalene. True or False?

Classify Triangles Lesson

More Printable Worksheets

Try the free Mathway calculator and problem solver below to practice various math topics. Try the given examples, or type in your own problem and check your answer with the step-by-step explanations. 