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1. Mornin,

I'm a little bit curious about using the formula. So for finding the area of a circle we use the normal formula, pi*r². But after doing this chapter, I wonder if you could do this one and get the same answer:

(r²*2pi)/2

The normal formula for finding the area of a sector is: half * r² * theta and I'm replacing the theta with 2pi, so for the hole circle (360° = 2pi radians)

Problem# 2:

If they give us in a question the area of the major sector and the angle of the minor sector, how can I find the radius?

2. 1) Simplify the new formula, it's exactly the same thing.

2) Major angle = 2pi - minor angle
area = r^2*major angle/2

rearrange to get a formula for r and substitute in.

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