MATH 1

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UNIT #1 EXERCISE #1

– BISECT A LINE

AS SHOWN IN CONSTRUCTION GEOMETRY TEXT

BISEC

T A LI

NEYou will need :-blank sheet of

paper-compass-ruler-pencil

step

by

step

Begin by drawing a straight line. We will call this line AB. This technique works with any line length, but I have chosen to draw my line 3” long.

Set your compass to any reasonable length greater than ½ of AB.

Cut an arc (draw a curved line) from point A (set the sharp point on A and make a curved line) above AB…

…and below AB

Now cut an arc (draw a curved line) from point B (set the sharp point on B and make curved lines) above and below AB, so that they intersect with the first pair of arcs (repeat the arcs from point B) using the same arc length.

Join the intersections (we will call them C and D) of the two sets of arcs with a straight line.

You are done!Line CD should meet line AB at right angles and bisect it (spilt it into to equal lengths).

RECAP:

NOTE:

CONDENSED STEP BY STEP:

1. 2. 3.

4. 5.

6. 7. 8.