What Is the Formula to Calculate the Angles of a Triangle?

Learn the simple formula to find any triangle's angles and how to calculate missing angles using basic geometry rules.

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To find the angles of a triangle, use the formula A + B + C = 180°, where A, B, and C represent the triangle's angles. If two angles are known, subtract their sum from 180° to find the third angle. For right triangles, if one acute angle is known, the other acute angle can be found by 90° - known angle.

FAQs & Answers

  1. What is the sum of the angles in a triangle? The sum of the interior angles in any triangle is always 180 degrees.
  2. How do you find the third angle if two angles of a triangle are known? Subtract the sum of the two known angles from 180 degrees to find the third angle.
  3. How do you calculate angles in a right triangle? In a right triangle, one angle is 90 degrees; if one acute angle is known, subtract it from 90 degrees to find the other acute angle.

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For more helpful math tutorials, check out our videos on calculating triangle areas, the Pythagorean theorem, and angle properties in polygons to deepen your understanding of geometry concepts.

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