Interior Angle Of Decagon

Diagonals are drawn from vertex a in the convex decagon below forming 8 triangles.

Interior angle of decagon. An interior angle is an angle inside a shape. A regular decagon has equal interior angle measures. Understanding the relationships that govern these angles is useful in various geometrical problems.

Sum of interior angles n 2 x 180 sum of interior angles 10 x 180 1800 once you know the sum you can divide that by 12 to get the measure of each interior angle. In terms of the apothem r see also inscribed figure. Since the sum of the angles of a triangle is 180 the sum of the interior angles of a dodecagon is 8 180 1440.

Each exterior angle for a regular decagon is 360o 10 36o. A decagon is a 10 sided polygon with 10 interior angles and 10 vertices which is where the sides meet. An irregular decagon has sides and angles that are not all equal or congruent.

Exterior and interior angles are supplementary that is sum to 180o. In particular it is helpful to know how to calculate the sum of interior angles in a polygon. Really clear math lessons pre algebra algebra precalculus cool math games online graphing calculators geometry art fractals polyhedra parents and teachers areas too.

Each angle measures 144 and they all add up to 1 440. Similarly 8 triangles can also be drawn in a concave decagon. The area of a regular decagon of side length a is given by.

A pentagon has 5 sides and can be made from three triangles so you know what. A regular decagon has 10 equal length sides and equal measure interior angles. Its interior angles add up to 3 180 540 and when it is regular all angles the same then each angle is 540 5 108 exercise.