Using just your compass and straight-edge, draw an angle that is as close to 30 degrees as possible. 45 degrees? 60 degrees?

I can use a compass and straight edge to draw 30, 45, 60, and 90 degree angles.

METHOD: Drawing a 60 degree angle

• Use your straight edge to draw a line segment

• Set your compass shorter than the segment and keep that setting for the remaining steps

• Draw an arc from the end of the line that crosses the line

• Set your compass on the intersection of the arc and line

• Draw an arc that crosses the first arc

• Connect the end of the line to the second arc intersection

Written instructions

Animation

METHOD: Drawing a 30 degree angle

• Draw a 60 degree angle

• Bisect the angle

Animation (angle bisector)

METHOD: Drawing a 90 degree angle

• Draw a line segment

• Draw the perpendicular line that goes through the end point

Animation (perpendicular through a point on a line)

METHOD: Drawing a 45 degree angle

• Draw a 90 degree angle

• Bisect the angle

Try this with a neighbor draw a 30, 45, 60, and 90 degree angle using your compass and straight edge. Create a set of steps for future reference as you work.

For your work today:

For a 3, turn in 2 of each angle (30, 45, 60, and 90). You MUST label each angle.

For a 4, can you figure out how to draw a 30-60-90 triangle using these methods? Draw one.