A wooden plate is shaped as a pentagon. The measure of one angle is 80°. The remaining interior angles are obtuse and of equal measure.

What is the measure of each obtuse angle in the pentagon?

Question

A wooden plate is shaped as a pentagon. The measure of one angle is 80°. The remaining interior angles are obtuse and of equal measure.  
 
What is the measure of each obtuse angle in the pentagon?

anonymous · Answer

115

anonymous · Answer

I see that a pentagon can be divided into 3 triangles.  Since each triangle has an angle sum of 180 that makes 540 degrees total.  We know that one angle is 80 so that leaves 540-80=460 for the remaining 4 angles.  Since 460/4=115, choose that answer.