1. CHAPTER 6
SECTIONS 7 AND 8

2. 6-7 PROPERTIES OF PARALLELOGRAMS
• A parallelogram is quadrilateral with two pairs of
parallel side.
B C
A D

3. 6-7 PROPERTIES OF PARALLELOGRAMS
• Name a pair
opposite sides.
B C • Name a pair of
opposite angles.
• Name a pair of
consecutive sides.
A D
• Name a pair of
consecutive angles.

4. 6-7 PROPERTIES OF PARALLELOGRAMS
• Draw four different parallelograms.
• Are there any lines of symmetry.
• Are there any sides or angles with the
same measure?
• Are there any supplementary angles?
• What can you say about the
diagonals.

5. 6-7 PROPERTIES OF PARALLELOGRAMS
• In parallelogram
B
ABCD, AB =
C
8, AD = 15.5, and
the measure angle
C = 360.
• Find CD, BC, and
the measure of
A D angles A, B, and D.

6. 6-8 THE TRIANGLE-SUM PROPERTY
• Draw any triangle on a scrap piece of
paper, use a straightedge.
• Tear off the three angles.
• Place the vertices of the three triangles
together.
• What do they form?
• What is the measure of that angle?
The sum of the measures of the three angles
of any triangle is 1800.