A triangle is created of three line segments. The line segments crossing in their endpoints. To name a triangle we regularly use that is vertices (the name of the endpoints). The triangle listed below is named ABC.

You are watching: A scalene triangle has how many congruent sides A triangle has actually three angles. The sum of the measures of the angle is constantly 180° in a triangle.

We have different varieties of triangles. A triangle is classified by the angles and also by the number of congruent sides.

A triangle that has actually three acute angels is referred to as an acute triangle. A triangle that has actually one best angle is referred to as a right triangle. A triangle that has actually one obtuse edge is dubbed an obtuse triangle. When a triangle has three congruent sides, we call the triangle an it is intended triangle. We note the congruent sides by a cut mark. The angle in an it is intended triangle are constantly 60°. When a triangle has actually two congruent political parties it is referred to as an isosceles triangle. The angle opposite come the 2 sides of the same size are congruent. A triangle without any kind of congruent sides or angle is referred to as a scalene triangle.

See more: How To Enter Serial Number In Photoshop Cc With Serial Number Video When 2 triangles room congruent it method that they have actually the very same size and shape. This means that they have the same angles. The red cut marks present us which sides and also angles that are congruent Congruency is displayed by this symbol

$$\cong$$ $$\beginmatrix A\cong X & & AB\cong XY\\ B\cong Y & & BC\cong YZ\\ C\cong Z & & AC\cong XZ \endmatrix$$

Triangles that have congruent angles yet not the exact same size are referred to as similar. Comparable triangles have actually sides that are proportional. Similarity is presented by this symbol

$$\sim$$ $$\bigtriangleup ABC\sim \bigtriangleup XYZ$$

$$A=X,\: \: B=Y,\: \: C=Z$$

$$\fracax=\fracby=\fraccz$$

Example

Find x in the comparable triangles. We understand that since the triangles are comparable the sides are proportional which means that

$$\fracx14=\frac321\Rightarrow$$

$$x=\frac14\cdot 321=\frac4221=2$$

$$x=2$$

## Video lesson

Find out whether the triangles room right, isosceles, acute, scalene, obtuse or equilateral