A regular octagon has 8 congruent interior angles. What is the measure of each angle?

Guest May 19, 2015

#2**+19 **

The formula for finding the sum of a polygon's interior angles is 180(n-2), where n is the number of sides/angles.

Thus, for an octagon:

Sum of interior angles = 180(8-2)

= 180(6)

= 1080

Since the 8 angles are congruent, simply divide 1080 by 8 for the measure of each angle:

1080/8 = 135 degrees

kitty<3
May 19, 2015

#1**+10 **

360 / 8 = 45° for each central angle.....the other two angles of each congruent triangle are 67.5° each

CPhill
May 19, 2015

#2**+19 **

Best Answer

The formula for finding the sum of a polygon's interior angles is 180(n-2), where n is the number of sides/angles.

Thus, for an octagon:

Sum of interior angles = 180(8-2)

= 180(6)

= 1080

Since the 8 angles are congruent, simply divide 1080 by 8 for the measure of each angle:

1080/8 = 135 degrees

kitty<3
May 19, 2015

#3**0 **

Kitty has done it via formula. There is nothing wrong with that. Thanks Kitty.

CPhill hse done it very logically, he just forgot to mention that 2 of his isoscles triangle 'leg' angles adds up to one internal ocatgon angels. His answer is the same as Kitty's.

I really like how you did that Chris.

Melody
May 19, 2015