interior angles - the angles between adjacent sides of a rectilinear figure

Consecutive Interior Angles

Shows you a proof of consecutive interior angles using parallel lines and a transversal

Janice says that the sum of the measures of the interior angles of an octagon is 900°. Is Janice cor

Janice says that the sum of the measures of the interior angles of an octagon is 900°. Is Janice correct? Why or why not?
She's [B]incorrect.
[/B]
The interior angle sum for a polygon is found with this formula:
Interior Angle Sum = (sides - 2) x 180°
Since an octagon has 8 sides, we have:
Interior Angle Sum = (8 - 2) x 180°
Interior Angle Sum = 6 x 180°
Interior Angle sum = 1080°

Polygons

Using various input scenarios of a polygon such as side length, number of sides, apothem, and radius, this calculator determines Perimeter or a polygon and Area of the polygon.
This also determines interior angles of a polygon and diagonals of a polygon as well as the total number of 1 vertex diagonals.