Right Obtuse And Acute Triangles

Related Pages
Types Of Triangles
Classifying Triangles
Classify Triangles past length of sides
Special Right Triangles
Area Of Triangles
More Geometry Lessons

Triangles classified by their angles

Triangles are polygons that have 3 sides, three vertices and three angles. I way to classify triangles is by the measure of their angles.

The following diagrams show the types of triangle based on sides. Scroll down the page for more examples and solutions of types of triangles.

types of triangles sides

Right Triangles

A right triangle is a triangle where ane of its angles is a correct bending (i.e. 90°). The other two angles are astute angles.

You may have noticed that the side reverse the right angle is always the triangle'southward longest side. Information technology is called the hypotenuse of the triangle. The other two sides are called the legs.

Right triangles are used in many branches of mathematics. For example, in trigonometry and besides in the Pythagorean Theorem. The lengths of the sides of a right triangle are related by the Pythagorean Theorem. There are also special right triangles where the sides are of certain fixed ratios.

right triangle

A right triangle tin be isosceles if the two legs are equal in length. A right isosceles triangle will have a 90º bending and two 45º angles.

A right triangle tin can not exist equilateral because the hypotenuse must e'er exist longer than the legs.

Astute Triangles

An acute triangle is a triangle whose angles are all acute (i.due east. less than 90°).

In the acute triangle shown below, a, b and c are all acute angles.

acute triangle

An equilateral triangle is always an astute triangle since all its angles are threescore° which are acute angles.

Obtuse Triangles

An obtuse triangle has one obtuse angle (i.east. greater than 90°). The longest side is always opposite the birdbrained bending. In the obtuse triangle shown below, a is the obtuse bending.

obtuse triangle

Since the sum of all the angles in a triangle is 180º, only ane angle in the triangle can be an obtuse angle, the other 2 angles must be astute angles.

Discover the six ways to classify triangles, both based on the measure out of their side lengths and past the measure of their angles

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The differences between the acute triangle, the right triangle and the obtuse triangle

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How to classify triangles - astute, obtuse, right?

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The Three Types of Triangles (Based on What Kinds of Angles They Have)

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