Question #3e595

1 Answer
Feb 18, 2018

Use the standard Euclidean construction tools.

Explanation:

I assume you are either given or can construct the circles with the given radii.

An essential tool is the ability to construct a perpendicular ("right") bisector of a line segment.

Given a line segment #PQ#
with center #P# and radius #abs(PQ)# draw a #color(red)("circle")#
with center #Q# and radius #abs(PQ)# draw a second #color(blue)("circle")#
* connect the two points where the circles intersect to form the right bisector.
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For any of the given circles:
draw any two distinct cords #color(red)(AB)# and #color(blue)(CD)#
draw the right bisector for each cord
* the point where the bisector lines intersect will be the center of the circle.

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For the given circle (and determined center #X#),
subdivide the circle into 6 equal arcs:
pick an arbitrary point #A# on the circumference of the circle.
with center #A# and circumference #AX# draw another circle
label the points where the new circle intersects the given circle as #B# and #F#
repeat this process using points #B# and #F# as centers (in place of #A#) to establish 2 more points #C# and #E#
* repeat this process one more time with center #C# (or #E#) to establish the 6th point.
The points #A, B, C, D, E, F# divide the circumference of the circle into 6 equal arcs.

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Using the arc end points
draw (extended) lines through pairs of points on opposite sides of the given circle; that is through #{A,D}# and through #{B,E}# and through #{C,F}#
draw lines perpendicular to those just constructed through the alternate points #B#, #D#, and #F#
These three new lines will intersect to form an equilateral, circumscribing triangle.
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