Find x in the following figures

Solution:

We know that the sum of the measures of the exterior angles of any polygon is 360°. So we will equate all the angle sum to 360° and find out the unknown angle.

(a)

Sum of the measures of the external angles,

125° + 125° + x° = 360°

250° + x° = 360°

x° = 110°

(b)

y = 180° - 90° [linear pair angles]

y = 90°

Sum of the measures of the external angles is 360°,

60° + 90° + 70° + x + y = 360°

60° + 90° + 70° + x + 90° = 360°

310° + x = 360°

x = 50°

☛ Check: Class 8 Maths NCERT Solutions Chapter 3

Video Solution:

Find x in the following figures
 

NCERT Solutions Class 8 Maths Chapter 3 Exercise 3.2 Question 1

Summary:

The value of x in the following figures are: (a) The value of x is 110°. (b) The value of x is 50°.

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