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Let the bottom left vertex of the equilateral triangle be (0,0)
In a 30-60-90 right triangle, the side opposite the right angle is [side opposite the 30° angle * 2 ] = [6 *2] = 12 = side of equilateral triangle
The side of the the right triangle opposite the 60° angle is [side opposite the 30° * √3 ] = [ 6√3 ] = √108
So....the top right vertex of the right triangle is ( 12 , √108 )
So...the distance that this vertex is from ( 0 , 0) is given by :
√ [ 12^2 + (√108)^2 ] =
√ [ 144 + 108 ] =
√ [252] =
√ [ 4 * 9 * 7 ] =
2*3 √7 =
6√7 units