1. Construct triangle ABC.

Choose points A, B, and C. Measure angle. =

Choose points A, C, and B. Measure angle. =

Choose points B, A, and C. Measure angle. =

Select the three measurements from the screen.

Measure (calculate) =

Move the triangle around, make it acute, right, and obtuse. Does the sum of the three angles stay the same? yes no

2. Construct line segment AB.

 Choose segment AB, construct "point on object", label as X.

Choose points A and X, construct "segment".

Choose points X and B, construct "segment".

Choose segment AX, measure "length". AX =

Choose segment XB, measure "length". XB =

Choose segment AB, measure "length". AB =

Using these measurements, prove that "segment addition" holds true.

3. Construct line segment XY.

Choose segment XY, construct "point at midpoint", label as M.

Choose points X and M, measure "distance". XM =

Choose points M and Y, measure "distance". MY =

Choose segment XY, measure "length". XY =

What does the midpoint of a segment do to the segment?

Make segment XY longer and shorter. Does your conjecture about the midpoint of a segment hold true? yes no

4. Construct an angle ABC. Make ABC = 70 degrees.

Choose points A, B, C. Construct "angle bisector".

Choose the angle bisector, construct "point on object", label as point D.

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=

=

What does the angle bisector do to the angle?

Make = 90 degrees. What does and equal?

Make = 140 degrees. What does and equal?

5. Construct a quadrilateral ABCD (4 sides).

=

=

=

=

The sum of the angles of a quadrilateral is .

6. Construct a pentagon ABCDE (5 sides).

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=

=

=

=

 The sum of the angles of a pentagon is .

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