the distance between the points A and B on the earth is measured along a circle having center C at the center of the earth and radius equal to the distance from C to the surface. If the diameter of the earth is approximately 8,000, approximate the distance between A and B if the angle ACB has measure 60°

Question

jdoe0001 · Answer

got picture?

anonymous · Answer

there isn't a picture

jdoe0001 · Answer

so we know the given diameter for a circle C is 8000
two points, A and B lie on the circle itself

there's an angle of 60 degrees between both points
so |dw:1404253006049:dw|    is that about right you think?

anonymous · Answer

yes

jdoe0001 · Answer

so we want to find the distance between A and B, that is |dw:1404253400860:dw|

jdoe0001 · Answer

so... notice firstly that the distance from C to B and from C to A is the radius and thus is the same, so CB = CA also recall that an isosceles triangle that has 2 equal sides, they make up 2 equal angles on the other end http://www.mathsisfun.com/definitions/isosceles-triangle.html

jdoe0001 · Answer

|dw:1404253715077:dw|    anyhow.... the only possible combination is 60, 60, 60

so the other 2 equal angles are also 60
60 + 60 + 60 = 180

what does that mean?    it means the last side is also 4,000