A triangle is written of three line segments. The line segments crossing in their endpoints. To surname a triangle we often use that is vertices (the name of the endpoints). The triangle listed below is called ABC.

You are watching: Can a scalene triangle have two congruent angles A triangle has actually three angles. The sum of the measures of the angles is always 180° in a triangle.

We have actually different types of triangles. A triangle is classified by that is angles and by the variety of congruent sides.

A triangle that has three acute angels is called an acute triangle. A triangle that has one best angle is dubbed a ideal triangle. A triangle that has actually one obtuse angle is dubbed an obtuse triangle. When a triangle has three congruent sides, we contact the triangle an equilateral triangle. We mark the congruent political parties by a slash mark. The angle in an it is provided triangle are constantly 60°. When a triangle has actually two congruent political parties it is referred to as an isosceles triangle. The angles opposite come the 2 sides the the same length are congruent. A triangle without any type of congruent sides or angles is called a scalene triangle.

See more: What Is Contour Plowing And How Does Contour Plowing Conserve Soil ? When two triangles are congruent it method that they have the exact same size and also shape. This way that they have the exact same angles. The red cut marks display us i beg your pardon sides and also angles that room congruent Congruency is presented by this symbol

\$\$cong\$\$ \$\$eginmatrix Acong X & & ABcong XY\ Bcong Y & & BCcong YZ\ Ccong Z & & ACcong XZ endmatrix\$\$

Triangles that have congruent angles but not the exact same size are dubbed similar. Similar triangles have sides that are proportional. Similarity is presented by this symbol

\$\$sim\$\$ \$\$igtriangleup ABCsim igtriangleup XYZ\$\$

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

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

Example

Find x in the similar triangles. We recognize that since the triangle are similar the sides are proportional which way that

\$\$fracx14=frac321Rightarrow\$\$

\$\$x=frac14cdot 321=frac4221=2\$\$

\$\$x=2\$\$

## Video lesson

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