Thursday

December 25, 2014

December 25, 2014

Posted by **Kaley** on Monday, May 17, 2010 at 4:54pm.

- Geometry -
**lily**, Monday, May 17, 2010 at 5:37pmi believe it would be 56.52 (not 100% positive though) because if the radius is 6, then the circumference would be 3.14(6^2)= 3.14(36) which is 113.04 then you would put that over 360 and set up a proportion:

113.04/360 = x/180 (simplified to 20347.2/360) which gives you a final answer of 56.52

hope this helps!

- Geometry -
**Reiny**, Monday, May 17, 2010 at 6:34pmThe height of the equilateral triangle will be a median in that triangle, and the centroid will be the centre of the circle.

That centroid splits the median in the ratio of 2 : 1

so the whole median, or the height of the triangle will be 9 in.

Half of the triangle will be a 30-60-90 triangle whose sides are in the ration of 1 : √3 : 2

9/√3 = b/1

so b = 9/√3 or the base is 18/√3

area of triangle = (1/2)(18/√3)(9) = 81/√3 or 27√3 or 46.765

Just thought of an easier way.

From the centre draw the 3 radii, giving us 3 congruent triangle with sides 6 and 6 and contained angle of 120°

Area of one of these = (1/2)(6)(6)sin120°

= 18(√3/2) = 9√3

but we have 3 of them, so the total equilateral triangle is 27√3

**Answer this Question**

**Related Questions**

geometry - The radius of the inscribed circle is equal to twice the area of the ...

geometry - Theres a circle with an equilateral triangle in the middle. The ...

geometry - An Equilateral triangle (ABC) is inscribed inside a circle. The side ...

geometry - The perimeter of a triangle, its area, and the radius of the circle ...

GEOMETRY CIRCLE - 1.An isosceles triangle with each leg measuring 13 cm is ...

GEOMETRY CIRCLES PLEASE - 1.An isosceles triangle with each leg measuring 13 cm ...

Algebra 2 - an equilateral triangle has an inscribed circle with a radius of ...

GEOMETRY CIRCLES - 1. Ab is a chord of a circle with center o and radius 52 cm...

Geometry about the circles - 1. Ab is a chord of a circle with center o and ...

Geometry about the circles - 1. Ab is a chord of a circle with center o and ...