DRILL• Identify whether the following

objects represent parallel lines, transversal lines, or both.

1. Window grills ( made of lines)2. Spider webs3. Bridge4. Legs of the chair5. highways

Opening activity

t

n

m

Describe the figure and the relationships

that exist between the lines & angles.

t m, t n

12

34

The numbered angles and its adjacent & supplementary

angles are all RIGHT ANGLES & therefore CONGRUENT.

What can you say about line m and line n?m // n

What are parallel lines?

t

n

m

In the figure, if line m is parallel to line n, then what do you call

line t?

Lines that are coplanar but never intersect.

Transversal line.A line that intersect two or more parallel lines at different points.

Opening activityd

b

k

Describe the figure and the relationships

that exist between the lines.

k //b, d is a transversal

Opening activityt

n

m1

6

2

57 8

What relationship exist between the following pairs of

angles.1 & 2, 3 & 41 & 3, 4 & 25 & 7, 5 & 67 & 8, 6 & 8

3 4They are ADJACENT and SUPPLEMENTARY.

Opening activityt

n

m1

6

2

57 8

What relationship exist between the following pairs of

angles.

1 & 4, 3 & 25 & 8, 6 & 7

3 4They are VERTICAL s and are CONGRUENT.

PAIRS OF ANGLES FORMED BY PARALLEL LINES CUT BY A TRANSVERSAL

MAIN ACTIVITY• Euclidian Geometry depends on

the supposition that parallel lines exist. This activity investigates what happens to the measures of corresponding angles when two lines are cut by a transversal. The investigation continues by exploring angle relationships that are formed when two parallel are cut by a transversal.

Main activityt

n

m

65

In the figure,

3 , 4, 5, & 6

are called INTERIOR ANGLES

3 4

Main activityt

n

m1 2

7 8

In the figure,

1, 7, 2 ,& 8are called EXTERIOR ANGLES

Main activityt

n

m

65

In the figure,

3 & 65, & 4

are called ALTERNATE INTERIOR ANGLES

3 4

Main activityt

n

m

65

3 4

- Two nonadjacent interior angles on the OPPOSITE side of a

transversal.

DESCRIBE ALTERNATE

INTERIOR ANGLES

Main activityt

n

m1 2

7 8

In the figure,1 & 8, 2 & 7

are called ALTERNATE

EXTERIOR ANGLES-Two nonadjacent exterior angles on the OPPOSITE side of a transversal

DESCRIBE ALTERNATE EXTERIOR ANGLES

Main activityt

n

m

65

In the figure,3 & 5, 4 & 6

are called CO-INTERIOR ANGLES

or SAME –SIDE INTERIOR ANGLES

3 4

- Two nonadjacent interior angles on the same side of a transversal.

DESCRIBE CO-INTERIOR ANGLES or SAME –SIDE INTERIOR ANGLES

Main activityt

n

m1 2

7 8

In the figure,1 & 7, 2 & 8

are called CO-EXTERIOR ANGLES

or SAME –SIDE EXTERIOR ANGLES

-Two nonadjacent exterior angles on the same side of a transversal

DESCRIBE CO-EXTERIOR ANGLES or SAME –SIDE EXTERIOR ANGLES

Main activityt

n

m1

6

2

57 8

In the figure,1 & 5, 3 & 72 & 6, 4 & 8

are called CORRESPONDING

ANGLES

3 4

- Two nonadjacent angles on the same side of a transversal such that one is an EXTERIOR

ANGLE and the other is an INTERIOR ANGLE.

Exercises

c

b

a 1

6

25

7

8

In the figure, a // b, c is a transversal line

34

Name two pairs of:

1.Consecutive angles

2.Alternate interior

angles.3. Alternate

exteriorangles

4. co- interior angles

5. Co –exterior angles

Exercises

c

b

a 1

6

25

7

8

In the figure, a // b, c is a transversal line

34

Name pairs of:

1.Corresponding angles

1 & 45 & 68 & 72 & 3

Exercises

c

b

a 1

6

25

7

8

In the figure, a // b, c is a transversal line

34

Name two pairs of:

2. Alternate interior

angles.

5 & 72 & 4

Exercises

c

b

a 1

6

25

7

8

In the figure, a // b, c is a transversal line

34

Name two pairs of:

3. Alternate Exterior

angles.

1 & 38 & 6

Exercises

c

b

a 1

6

25

7

8

In the figure, a // b, c is a transversal line

34

Name two pairs of:

4. Co- Exterior angles.

1 & 68 & 3

Exercises

c

b

a 1

6

25

7

8

In the figure, a // b, c is a transversal line

34

Name two pairs of:

5. Co-interior angles.

5 & 42 & 7

QUIZ

•Get ¼ sheet of paper

QUIZ

c

b

a 2

7

41

6

3

In the figure, a // b, c is a transversal line

85

Name two pairs of:

1.Corresponding angles

2.Alternate interior

angles.3. Alternate

exteriorangles

4. co- interior angles

5. Co –exterior angles

Assigment • In the figure, identify and name the

pairs of parallel lines and its transversal.

B

F

A

C D G

E