Question

Find the value of 'a' in each of the following:
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Answer 1

SoluTion :-

(i) The angle is right angle, i.e, 90°

Value of a = 90° - 60°

= 30°

(ii) The angle is straight angle, i.e, 180°

Value of a = 180° - 63°

= 117°

(iii) The angle is straight angle, i.e, 180°

So, 180° = 90° + (a + a)

Or, 180° = 90° + 2a

Or, 180° - 90° = 2a

Or, 90° = 2a

Thus, a = 90/2

a = 45°

(iv) The angle is straight angle, i.e, 180°

So, 3a + 2a + 3a = 180°

Or, 8a = 180°

Or, a = 180/8

Thus, a = 10°

Answer 2

Answer:

Step-by-step explanation:

1. 180=60+a

      a=180/60

      a=30

2.180=63+a

      a=180/63

      a=20/7

3.180=90+a+a

    2a=180/90

    2a=20

      a=20/2

      a=10

4.180=3a+2a+3a

    8a=180

      a=180/8

      a=22.5

therefore,

3a=3x22.5

   =67.5

2a=2x22.5

   =45

3a=3x22.5

   =67.5