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What will be the diameter of the circle with seven chords 1.25 inches in length.

I want to draw seven pointed stars on my wall representing the Southern Cross.
Thanks Richard.

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Parviz F. | Mathematics professor at Community CollegesMathematics professor at Community Colle...
4.8 4.8 (4 lesson ratings) (4)
 Central angle of each sector = 360/ 7 = 51.4°
  Sin (51.4 ° / 2) = (1.25/ 2 )/ r
   Sin( 25.7°) = 0.625 r
      0. 43/ 0.625 = r
        r/2 = 0.69
        d = 4(0.69) = 4( 0.69) = 2.79"
     This is a trigonometry problem . You should draw a sector of 51.4° degree, and see the rissoles triangle
     with 2 sides equal the radius, and the central angle of 51.4°. 


If I scribe a circle with a diameter of 1.38 inches how can this circle house a regular polygon with seven equal sides of 1.25 inches?
Thanks for your answer Parviz F. I think it is close to exact. Trig tables can differ I have noticed so that may account for the slight error. Another answer is 2.880 inches from Moneypenny, a dreadful speller by the way, if she is there. Get that head of yours into a good English dictionary.
Parvis F, as for you spelling of the isosceles triangle, well you might well Google types of triangles. There are only three and they must be spelt correctly.