MODULE I VOCABULARYPART IV

CONSTRUCTION SITE

• The first construction we’ll discuss is copying a line segment.

CONSTRUCTION SITE

1. Place the ends of your compass on the ends of the segment to be copied and lock in the length.

2. Place the pointy end on the new endpoint and make an arc with the drawing end.

3. Make a dot on that arc.4. Connect the dots.

CONSTRUCTION SITE

http://www.mathopenref.com/constcopysegment.html

CONSTRUCTION SITE

• Copy the segment below.

CONSTRUCTION SITE

• The next construction is copying an angle.

CONSTRUCTION SITE 1. Place the pointy end on the given angle’s vertex

and make an arc that crosses both rays. Make a dot where the arcs cross the angle

2. Keeping that length locked in, place the pointy end of your compass on an endpoint of the new segment and make an arc that crosses it.

3. Place the pointy end and the drawing end on the two points on the old angle where the arc touches the angle

CONSTRUCTION SITE

4. Lock in that length and place the pointy end on your line segment and arc intersection.

5. Make an arc.6. Where the new arc crosses the old arc, make

a dot.7. Connect your vertex to the new intersection.

CONSTRUCTION SITE

http://www.mathopenref.com/constcopyangle.html

CONSTRUCTION SITE

• Copy the angle.

CONSTRUCTION SITE

• The next construction we’ll discuss is also one of the easiest…a perpendicular bisector.

CONSTRUCTION SITE 1. Place the pointy end of your compass on an

endpoint of the segment.2. Ensure that the drawing end is a bit past the

halfway point of the segment and make a semi-circle.

3. Keeping that length locked in, repeat step #2 for the other endpoint.

4. Draw and connect the intersections of the two arcs.

CONSTRUCTION SITE

http://www.mathopenref.com/constbisectline.html

CONSTRUCTION SITE

• Construct the perpendicular bisector of the line below.

CONSTRUCTION SITE

• To construct a regular perpendicular line, you simply don’t use the endpoints for your places for the line.

CONSTRUCTION SITE

• The next construction is an angle bisector.

CONSTRUCTION SITE 1. Make an arc with the pointy end of the

compass on the vertex. The arc should touch both rays.

2. Now place the pointy end on the intersection of the ray and the arc and make another arc. Repeat for the other intersection.

3. There should be an intersection of arcs in the middle of the angle. Connect it with the vertex.

CONSTRUCTION SITE

http://www.mathopenref.com/constbisectangle.html

CONSTRUCTION SITE

• Construct the bisector of the angle below.

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• Lastly, we construct parallel lines.

CONSTRUCTION SITE

1. First we draw a line which intersects the point and the line.

2. Draw a small arc from the intersection on the line and another (with the same length) from the point and on the line.

3. From that intersection, measure the length to the arc intersection and copy that onto the upper arc.

CONSTRUCTION SITE

4. Connect the intersection and the point to form the parallel line.

CONSTRUCTION SITE

http://www.mathopenref.com/constparallel.html

CONSTRUCTION SITE

• Construct a line parallel to the line below.