please help:) The measure of one angle of an octagon is twice that of the other seven angles. What is the measure of each angle?

The sum of all angles in an octagon is given by

180*(n-2) >>>>>>>>>with n = 8

180*(8-2) = 1080 degrees

A + B = 1080 .......where

A  is the angle of an octagon which is twice that of the other seven angles

B equals the sum of the other seven angles

If we assume each angle of B is equal to each other, then

B = x+x+x+x+x+x+x = 7x

And A = 2x

The equation that results is 

A + B = 2x +7x = 9x =1080

x = 120 degrees
2x = A = 240 degrees