SOLUTION: Three angles of an irregular octagon are 100,120,140degrees.The remaining angles are congruent.find the size of each of the remaining angles.

Question 1108828: Three angles of an irregular octagon are 100,120,140degrees.The remaining angles are congruent.find the size of each of the remaining angles.
Answer by ikleyn(52835) (Show Source): You can put this solution on YOUR website!
.

100 + 120 + 140 + (8-3)*x = (8-2)*180   degrees.   <<<---=== Each side is the sum of interior angles of the octagon.


Simplify and solve for x:


360 + 5x = 6*180,

5x = 6*180 - 360 = 720  ====>  x =  = 144.


Answer.  144 degrees.

-----------
To see other similar solved problems, look into the lessons
    - Solved problems on supplementary and complementary angles
    - Solved problems on angles of a triangle
    - Solved problems on angles of a parallelogram
    - Solved problems on angles of a quadrilateral
    - Solved problems on angles of a polygon
    - Solved problems on missed angle of a polygon
    - Solved problems on angles of a regular polygon
in this site.

Also, you have this free of charge online textbook on Geometry
    GEOMETRY - YOUR ONLINE TEXTBOOK
in this site.

The referred lessons are the part of this online textbook under the topic "Finding angles of triangles, parallelograms and rectangles".

Save the link to this online textbook together with its description

Free of charge online textbook in GEOMETRY
https://www.algebra.com/algebra/homework/Triangles/GEOMETRY-your-online-textbook.lesson

to your archive and use it when it is needed.

RELATED QUESTIONS
An octagon has two equal angles each 120� and all the remaining six angles are equal.... (answered by dkppathak)

One of the angles of an octagon is 86 degrees., if the remaining angles are all equal,... (answered by Alan3354)

An octagon has eight interior angles, five of which sum to 845 degrees. Two of the... (answered by cleomenius)

An octagon has angles of 120,140,170,& 165. The other angles are all equal. find their... (answered by fractalier,addingup)

All of the angles in a regular octagon are congruent. what is the measure of each angel,... (answered by ewatrrr)

One angle of a triangle measures 120 degrees. The other two angles are congruent. Write... (answered by rfer)

1.) two angles of a quadrilateral are congruent and each of their measures is 110. what (answered by stanbon)

3 angles of an octagon are x each.if the other angles are 20 more than each of the other (answered by stanbon)

Three of the exterior angles of an n-sided polygon are 15, 25, 70, and the remaining... (answered by Edwin McCravy)