Question

3. In the following questions, the measures of two angles are given. In each case find the measure
the third angle:
(1) 30°. 80
(11) 40°. 40
(iii) 20°. 70
(iv) 59.45
(v) 35 116​

Answer 1

Answer:

1. 70°
2. 100°
3. 90°
4. 76°
5. 29°

Step-by-step explanation:

1. 30° 80°

Soln- Let the other angle be x.

Given that, the other two angles are 30° 80°

Then, by using Angle-sum property of,

triangle, we have,

30° + 80° + x = 180°

110° + x = 180°

Therefore, x = 180° - 110°

= 70°

Hence the third angle is 70°.

11. 40° 40

Soln- Let the other angle be x.

Given that, the other two angles are 30° 80°

Then, by using Angle-sum property of,

triangle, we have,

40° + 40° + x = 180°

80° + x = 180°

Therefore, x = 180° - 80°

= 100°

Hence the third angle is 100°.

iii. 20° 70

Soln. Let the other angle be x.

Given that, the other two angles are 30° 80°

Then, by using Angle-sum property of,

triangle, we have,

20° + 70° + x = 180°

90° + x = 180°

Therefore, x = 180° - 90°

= 90°

Hence the third angle is 90°.

iv. 59° 45°

Soln. Let the other angle be x.

Given that, the other two angles are 59° 45°

Then, by using Angle-sum property of,

triangle, we have,

59° + 45° + x = 180°

104° + x = 180°

Therefore, x = 180° - 104°

= 76°

Hence the third angle is 76°.

v. 35° 116°

Soln.

Let the other angle be x.

Given that, the other two angles are 35° 116°

Then, by using Angle-sum property of,

triangle, we have,

35° + 116° + x = 180°

151° + x = 180°

Therefore, x = 180° - 151°

= 29°

Hence the third angle is 29°.

Answer 2

Answer:

1 30 + 80 = 180

180-110