Question

Angle calculation.

Answer 1

Since it is a regular octagon, I know that a = 135 degrees

Answer 2

now find b

Answer 3

b=40

Answer 4

I can see how to find d. the angle of the base of the isosceles triangle is 45
that makes the angle at the apex 90. 90+135+d= 360

Answer 5

find d now.

Answer 6

well d would have to be 135 degrees.

Answer 7

the other side of 135 ... can you find it?

Answer 8

sorry .. 150

Answer 9

mmmm yeah. it should be 30 degrees.

Answer 10

what is the alternate angle of of that 30 degree?

Answer 11

the supplementary to c.

Answer 12

yea ... use that to find the value of c

Answer 13

Well then c=150....but that doesn't seem quite correct if you are looking at the diagram.

Answer 14

Oh.....because it's not. We have to subtract 70 from 180 to find c because we have to include b also. so c=110

Answer 15

find these two angles ... they are equal since it's an isoscles triangle