How to find the area of a circle when given the circumference?

1. C = 2 π r

2. r = C / (2 π)

3. A = π [C / (2π)] 2

4. A = C2 / (4 π)

I hope this helps you out because I only write them by equation rather than in words.

PS ≅ FK, RF ≅ GP ∠R ≅ ∠G

Solution:

Given in ΔKFR, KF = 10, FR = 16, KR = 20

In ΔGPS, GP = 8, GS = 10, PS = 5

In the given image the two triangles are similar.

That is, ΔKFR ≅ ΔGPS

We know that the corresponding parts of the similar triangles are congruent.

(1) ∠F ≅ ∠P (given)

So, PS ≅ FK

(2) ∠R ≅ ∠G (given)

∠F ≅ ∠P (given)

So, RF ≅ GP

(3) ∠R ≅ ∠G (given in the image)

Hence PS ≅ FK, RF ≅ GP ∠R ≅ ∠G.