Download Duplicating Segments and Anlges

Duplicating Segments and Anlges
Objective: Students will use a
compass and straight edge to copy
and construct segments and angles.
Types of Pictures
Sketch – freehand drawing of something, sketch
a right triangle, not exact
Drawing – using tools to accurately measure
lengths and angles
Construction – using a compass and straight
edge, not exact measurements, neater than a
sketch but not as accurate as a drwaing
Duplicating a Segment
Investigation pg 145
Process
1. Draw a ray, this should be longer then
segment you are constructing
2. Place pointy end of compass on one
endpoint and pencil on the other – this is
measuring the distance using a compass
3. Place the pointy end of compass on endpoint
of ray, swing arc so it intersects the ray
4. Mark the intersection with a point
Multiple Segments
How would you combine multiple segments or
subtract?
Duplicating an Angle
Investigation pg 146
Process
1. Draw a ray
2. Place pointy end of compass on vertex of the angle then
swing an arc so it intersects both sides – there is already
an arc to use when copying an angle from the book
3. Put pointy end of compass on the endpoint of ray and
swing the arc from step 2, make sure it crosses the ray and
goes more than what the angle look
4. On original angle place the pointy end of compass on one
intersection and place pencil on second intersection – this
measure the distance of the arc
5. Place pointy end of compass on intersection of arc and
ray, swing compass until two arcs intersect
6. Connect endpoint and intersection
Multiple Angles
How would you combine multiple angles or
subtract?
Objective: Students will use a compass and
straight edge to copy and construct segments
and angles.
On a scale of 1 to 4 Do you feel we meet the
objective for the day.
If we did not meet the objective, what did we
miss and how could I improve.
Homework
Pg 147 1-4 and 8