A parallelogram is a quadrilateral with two pairs of parallel sides. It has two pairs of opposite sides and angles. Its consecutive sides and angles also form pairs. Parallelograms have lines of symmetry and sides or angles with the same measure. Their diagonals bisect each other. The document also discusses using properties of parallelograms to find missing side lengths and angle measures, and explains that the sum of the three interior angles of any triangle is always 180 degrees.
Properties of Parallelograms
Properties of Parallelograms
Properties of Parallelograms
Properties of Parallelograms
Properties of Parallelograms
Properties of Parallelograms
Properties of Parallelograms
Properties of Parallelograms
Properties of Parallelograms
Properties of Parallelograms
Properties of Parallelograms
Properties of Parallelograms
Properties of Parallelograms
Properties of Parallelograms
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.