Subject: Circle Problem Driving me mad...
Christopher
Grade 10 Student
Attached to this email is the diagram that goes with my problem.
Inside the quartercircle are two semicircles with the same radius, (r). Which has a greater area, G or L?
Thanks in advance.
Hi Christopher,
You can write the area of the quartercircle since you know its radius is 2r. You can also write the areas of the two semicircles since you know each has radius r. The result follows from the observation that the area of the quartercircle ABC is equal to the area of the semicircle on AB plus the area of the semicircle ob BC minus the area of L plus the area of G. (You need to subtract the area of the region L since in adding the areas of the two semicircles you included L twice.)


Cheers,
Penny