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I can get as far as to work out the angles inside the triangle and to work out the perimeter of the circle (except for the triangle) but that's it. Can ya show me step by step how to do this? Thanks!

 Dec 17, 2018
 #1
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The triangle is isoceles......each of the smaller angles = 30°

 

To find the straight edge length we can use the Law of Sines

 

Edge Length / sin120°  = 60/ sin 30°

 

Edge Length  =   60*sin (120°) / sin 30°  = [60sqrt (3)/2] / (1/2)  = 60sqrt(3) cm   (1) 

 

For the curved part.....the perimeter is

 

(240/360) * 2 * pi * (60)  =

 

(4/3) * pi * 60  =

 

80 pi  cm    (2)

 

So....the perimeter is (1) + (2)   =

 

[ 60sqrt(3) + 80 pi ] cm ≈   355.25 cm

 

 

cool cool cool

 Dec 17, 2018

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