Exercise 30 Page 404

The sum of the measures of the interior angles of a polygon is (n-2)180, where n represents the number of sides.

1080^(∘)

Practice makes perfect

Let's start by recalling the rule for the sum of the measures of the interior angles of a polygon.

Interior Angle Sum of a Polygon
The sum of the measures of the interior angles of a polygon is (n-2)180, where n represents the number of sides.

To find the sum of the measures of the interior angles of an octagon, we will substitute 8 for n in this expression.

(n-2)180

n= 8

( 8-2)180

▼

Evaluate

Subtract term

(6)180

1080

The sum of the interior angles of an octagon is 1080^(∘).

Guided Practice p.400

Independent Practice p.401-402

H.O.T. Problems p.402

Standardized Test Practice p.402-404

Extra Practice p.403

Common Core Review p.404

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