Triangles Math Example 1

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Example 1

easy
Two angles of a triangle measure 50°50° and 65°65°. Find the third angle.

Solution

  1. 1
    The angle sum property states that all angles in a triangle add up to 180°180°.
  2. 2
    Let the third angle be xx: 50+65+x=18050 + 65 + x = 180.
  3. 3
    Solve: x=180−115=65°x = 180 - 115 = 65°.

Answer

x=65°x = 65°
The triangle angle sum property (180°180°) is one of the foundational facts in geometry. Since two angles are 50°50° and 65°65°, and the third is also 65°65°, this is an isosceles triangle.

About Triangles

A polygon with exactly three sides and three interior angles that always sum to exactly 180 degrees.

Learn more about Triangles →

More Triangles Examples

Example 2 medium

Classify the triangle with sides [formula] cm, [formula] cm, and [formula] cm by its sides and deter

Example 3 easy

An equilateral triangle has a perimeter of [formula] cm. Find the length of each side.

Example 4 medium

The three angles of a triangle are in the ratio [formula]. Find the measure of each angle.

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