Polygon Formulas Warm Up

"Find the sum of the interior angles of a regular octagon."

Which formula would you use?

• Sum e=360

• e = 360/n

What is the sum of the interior angles of a regular Octagon?

• 1080 degrees

• 180 degrees

• 360 degrees

• 135 degrees

"Find each exterior angle of a regular pentagon."

Which formula would you use?​ ​ (a)  

• e=360/n
• Sum e=360
• i= Sum i/n
• n= 360/e

What is the measure of each exterior angle of a pentagon?​ (a)  

• 72 degrees
• 360 degrees
• 108 degrees
• 180 degrees

What does n represent in a polygon formula?

• One interior angle

• Number of angles

• Number of sides

• One exterior angle

What is the sum of the exterior angles of a 20-gon?

• 180 degrees

• 3240 degrees

• 162 degrees

• 360 degrees

Match the following formulas to the key words...

• Find each interior angle...

• What is the sum of the exterior angles of...?

• Find the sum of the interior angles...

• What is the number of sides...?

• Find one exterior angle...

e represents what in a polygon formula?

• extra

• exterior angle

• element

• enthusiasm

Sum i means...

• Sum of increase

• Sum of interior sides

• Sum of interior angle measures

• Sum instantaneous

How many sides does a heptagon have ?​ (a)  

• 7
• 6
• 12
• 0
• 9