Question

Help please, I can't find what angle AOC is.

Answer 1

oops are there any parallel lines

Answer 2

there are no parallel lines. Well from the book anyway.

Answer 3

It says, The circle with center at C has a radius r units. Angle ABC measures 15 degrees and angle ADC measures 55 degrees. Find angle AOC.

Answer 4

ok... here is is

in triangle CAD

CD = CA equal radii

so the triangle is isosceles

then angle CDA = CAD so CAD = 55 base angles of an isosceles triangle

and DAC = 70.

now

in triangle CBD

CD = CB equal radii

so triangle CBD is also isosceles

then angle CBD = angle CDB

so

CBD = 15

now you can find AOC by angle sum of a triangle

hope it makes sense

Answer 5

Ohh, I'll still have to take it in but you get it right. It says 95 here also in the answer sheet. Thank you.

Answer 6

Don't worry, It made perfect sense.. You have my thanks sir. How could have isosceles triangle not come into mind? >. <