ANGLE AND LINE

By:NIKMATUL HUSNA

SUPPLEMENTARY

AOC + BOC = AOB a0 + b0 = 1800

We can write a0 = 1800 - b0 or b0 = 1800 - a0

Conclusion :

• The sum of supplementary angle is 1800.

• An angle is the supplement of another angle

COMPLEMENTARY

PQS + RQS = PQR X0 + Y0 = 900

We can write X0 = 900 - Y0 or Y0 = 900 - X0

Conclusion :

• The sum of complementary angle is 900.

• An angle is the complement of another angle

OPPOSITE ANGLE

ÐPOQ = SORÐPOS = QOR

ÐPOQ and SOR are opposite angle.ÐPOS and QOR are opposite angle.

Conclusion :

• The measure of opposite angle is same

Opposite Angles

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5 6 7 8t

1 and 7 2 and 83 and 54 and 6

1 = 7, 2 = 8, 3 = 5, 4 = 6

a. Corresponding Anglesb. Alternate Interior Anglesc. Alternate Exterior Anglesd. Consecutive Interior Anglese. Consecutive Exterior Angles

1234

5 6 7 8t

Corresponding Angles

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5 6 7 8t

4 and 2 3 and 15 and 76 and 8

4 = 2, 3 = 1, 5 = 7, 6 = 8

Alternate Interior Angles

3 and 72 and 6

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5 6 7 8t

3 = 7 and2 = 6

Alternate Exterior Angles

5 and 14 and 8

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5 6 7 8t

5 = 1 and4 = 8

Consecutive Interior Angles

3 and 26 and 7 1

2345 6 7 8

t

3 +2 = 1800 and 6 +7 = 1800

Consecutive Exterior Angles

4 and 15 and 8 1

2345 6 7 8

t

4 + 1 = 1800 and 5 + 8 = 1800

Look at the picture.Given 1 = 750 and Find:Ð1 5Ð2 6Ð3 7Ð4 8

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5 6 7 8t

Example :

Ð1 = 750 5 = 750 Ð2 = 1050 6 = 1050

Ð3 = 750 7= 750

Ð4 = 1050 8= 1050

Answer :

Look at the picture.Given 1 = (3x+45)0 and 4 =(5x+23)0 . Find:Ð1 5Ð2 6Ð3 7Ð4 8

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5 6 7 8t

Example :

Answer :

Ð1 + 4 =1800 (3x+45)0 + (5x+23)0 =1800

3x 0+ 5x 0 +45 0 + 23 0 =1800

8x0 =1800- 450 – 230

8x0 =112 0

x = 140

Ð1=(3x+45)0

= 3 X 140 +450 = 420 +450 = 870

4=1800- 870 = 930

2= 930

3= 870

5= 870

6= 930

7= 870

8= 930