Finding the Area of each Shaded Sector...

[LoU LoU ♥]

I am a little confused on doing these...Any help would be appreciated...I just dont understand why you have to find the area of the circle...then the sector...and then the triangle..Then subtract those two values....I keep getting the wrong answer...I am really confused!!

 

[pka]

We need a diagram to understand the problem!
Please post a figure or a compete description of the problem

 

[Lou Lou]

Ok...Given circle O...with shaded sector...DOE...the central arc of DOE is 45 degrees....the radius...(DO) is 8 inches....I dont know how else to describe it the drawing...
Can you give me step by step instructions on how to do this...?

 

[Lou Lou]

so..do i just do 120/360 * 4^2(pi)
and thats the area of the sector...im confused!!

 

[Gene]

You said the radius was 8" so the area of the circle is 8^2*pi. There are 360° in it. Think of a pie with 8 slices. Each piece (sector) has a central angle of 45°. That is 45/360 = 1/8 the of the pie so it is 1/8 of the area of the whole pie. If it were a 12 piece pie each would be 30° and each piece is 30/360 = 1/12 the area.