## Three angles of an irregular octagon are 100 degrees, 120 degrees, and 140 degrees. The remaining angles are congruent. Find the size of eac

Question

Lost your password? Please enter your email address. You will receive a link and will create a new password via email.

## Answers ( )

Answer:144°

Step-by-step explanation:The sum of the interior angles of a polygon is

sum = 180° × (n – 2) ← n is the number of sides

Here n = 8 ( octagon ), hence

sum = 180° × 6 = 1080°

let the measure of 1 congruent angle be x

Then sum the 8 angles and equate to 1080

100 + 120 + 140 + 5x = 1080

360 + 5x = 1080 ( subtract 360 from both sides )

5x = 720 ( divide both sides by 5 )

x = 144

Thus each of the 5 congruent angles is 144°