6-2 Parallelograms

20
6-2 Parallelograms You classified polygons with four sides as quadrilaterals. Recognize and apply properties of the sides and angles of parallelograms. Recognize and apply properties of the diagonals of parallelograms.

description

You classified polygons with four sides as quadrilaterals. 6-2 Parallelograms. Recognize and apply properties of the sides and angles of parallelograms. Recognize and apply properties of the diagonals of parallelograms. Parallelogram Probe. Draw diagonals in your parallelogram. - PowerPoint PPT Presentation

Transcript of 6-2 Parallelograms

Page 1: 6-2 Parallelograms

6-2 Parallelograms

You classified polygons with four sides as quadrilaterals.

• Recognize and apply properties of the sides and angles of parallelograms.

• Recognize and apply properties of the diagonals of parallelograms.

Page 2: 6-2 Parallelograms

Parallelogram Probe

1. Draw diagonals in your parallelogram.

2. Measure the sides.

3. Measure the diagonals.

4. Measure the diagonal parts.

5. Measure the angles.

Page 3: 6-2 Parallelograms

Page 403

Page 4: 6-2 Parallelograms

Page 404

Page 5: 6-2 Parallelograms

A. CONSTRUCTION In suppose mB = 32, CD = 80 inches, BC = 15 inches. Find AD.

AD = BC Opposite sides of a are .

= 15 Substitution

Answer: AD = 15 inches

Page 6: 6-2 Parallelograms

B. CONSTRUCTION In suppose mB = 32, CD = 80 inches, BC = 15 inches. Find mC.

Answer: mC = 148

mC + mB = 180 Cons. s in a are supplementary.

mC + 32 = 180 Substitution

mC = 148 Subtract 32 from each side.

Page 7: 6-2 Parallelograms

C. CONSTRUCTION In suppose mB = 32, CD = 80 inches, BC = 15 inches. Find mD.

Answer: mD = 32

mD = mB Opp. s of a are .

= 32 Substitution

Page 8: 6-2 Parallelograms

A. 10

B. 20

C. 30

D. 50

A. ABCD is a parallelogram. Find AB.

Page 9: 6-2 Parallelograms

A. 36

B. 54

C. 144

D. 154

B. ABCD is a parallelogram. Find mC.

Page 10: 6-2 Parallelograms

A. 36

B. 54

C. 144

D. 154

C. ABCD is a parallelogram. Find mD.

Page 11: 6-2 Parallelograms

Page 405

Page 12: 6-2 Parallelograms

Find the following in parallelogram MNOP

d. MP =

e. OP =

f. MQ =

g. NQ =

PMNm.a

MNOmc.OPMmb.

M N

OP

Q

135°

7

15

NP = 21

MO = 11

135°

45°

7

45°

15

5.5

10.5

Page 13: 6-2 Parallelograms

A. If WXYZ is a parallelogram, find the value of r.

Opposite sides of a parallelogram are .Definition of congruence

SubstitutionDivide each side by 4.

Answer: r = 4.5

Page 14: 6-2 Parallelograms

B. If WXYZ is a parallelogram, find the value of s.

8s = 7s + 3 Diagonals of a bisecteach other.

Answer: s = 3

s = 3 Subtract 7s from each side.

Page 15: 6-2 Parallelograms

A. 2

B. 3

C. 5

D. 7

A. If ABCD is a parallelogram, find the value of x.

Page 16: 6-2 Parallelograms

A. 4

B. 8

C. 10

D. 11

B. If ABCD is a parallelogram, find the value of p.

Page 17: 6-2 Parallelograms

What are the coordinates of the intersection of the diagonals of parallelogram MNPR, with vertices M(–3, 0), N(–1, 3), P(5, 4), and R(3, 1)?

Since the diagonals of a parallelogram bisect each other, the intersection point is the midpoint of

Find the midpoint of

Midpoint Formula

Answer: The coordinates of the intersection of the diagonals of parallelogram MNPR are (1, 2).

Page 18: 6-2 Parallelograms

Properties of Parallelograms• The opposite sides of a parallelogram are

parallel (by definition).• The opposite angles of a parallelogram are

congruent.• The opposite sides of a parallelogram are

congruent.• The consecutive angles of a parallelogram

are supplementary.• The diagonals of a parallelogram bisect each

other

Page 19: 6-2 Parallelograms

• What is true about the opposite sides of a parallelogram?

They are parallel and congruent.

• What is true about the opposite angles?

They are congruent.

• What is true about the consecutive angles?

They are supplementary.

• What is true about the diagonals?

They bisect each other.

Page 20: 6-2 Parallelograms

6-2 Assignment

• Page 407, 9-12,