6th Grade Math Textbook, Progress

Line Constructions

10-5

Step 1

Draw a ray with

endpoint C.

Step 2

Open the compass

to the length of AB
.

Step 3

With the same compass setting, put

the compass point on C. Construct an

arc that intersects the ray. Label the

intersection D.

CD

AB

A construction is a geometric drawing that is made using only an

unmarked straightedge and a compass. A compass is a geometric

tool used to draw a circle or a part of a circle, called an arc.

To construct a line segment, CD, congruent

to a given line segment, AB:

To construct the perpendicular bisector of a line segment, AB:

Given: AB

Step 1

Put the compass point

on point Aand construct

an arc. Be sure the

opening is greater than

^12
AB
. Keep the same

compass setting for Step 2.

Step 2

Put the compass point on

point Band construct an

arc. Label the points

where the two arcs

intersect as Xand Y.

Step 3

Draw XY. Label the

intersection of AB
and

XYas point M.

XYis the perpendicular

bisector of AB
. Point Mis

the midpoint of AB
.







AB

C

AB

C D

AB

X

Y

AB

X

Y

AB

M

AB

Given: AB

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