Construct a Regular Polygon
You can construct a regular polygon by using a circle.
To construct a regular hexagon, follow these steps.
Construct each regular polygon by using a circle. Explain your process.
- an equilateral triangle 21.a square 22. a regular dodecagon
A regular polygon has
congruent sides and
congruent angles.
Step 1
Use a compass to
construct a circle. Put
the compass point
anywhere on the circle.
With the same radius
as the circle, construct
an arc that intersects
the circle at point A.
Step 3
Repeat Step 2 all the way
around the circle. Label
the points of intersection
C, D, E, and F. With a
straightedge, draw the
segments joining the
points. ABCDEFis a
regular hexagon.
For each statement, write always, sometimes, ornever.
- All radii of a circle have the same length.
- Chords are diameters.
- A central angle has its vertex on
the circle.
Use a compass to construct a circle. Then do the following:
- Draw and label the diameter AB.
- Draw the chords ACand BC.
24. Circle Xhas two intersecting diameters, AB
and CD. If mAXC75°, what are the
measures of the other three central angles? - Draw any point C on the circle.
- Name the figure you have drawn.
- Some arcs are line segments.
- All circles are regular polygons.
- The longest chord of any circle
is its diameter. - Alex draws circle Owith a diameter
of 12 inches. What is the length of a
radius of the circle O?
Step 2
With the same radius
as the circle, put the
compass point at Aand
construct another arc
that intersects the circle
at point B.
A A
B
A
D C
E
F
B
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