NCERT Solutions of Quadrilaterals Class 9
<< Solution of NCERT math Exercise 3.1 (Part 1)Solution of NCERT Exercise 3.2 >>

Understanding Quadrilateral

Solution of NCERT math Exercise 3.1 (part 2)

Question 6 Find the angle measures x in the following figures.

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Solution:

We know that, angle sum of a quadrilateral = 360

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Question - 6 (b)

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Solution:

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We know that, angle sum of a quadrilateral = 360

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Question - 6 (c)

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Solution:

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Question - 6 (d)

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Solution:

Angle sum of a pentagon = (5 2) x 180 = 3 x 180 = 540

Since, it is a regular pentagon, thus, its angles are equal

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Question 7

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Solution:

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We know that angle sum of a triangle = 180

Thus, 30 + 90 + C = 180

Or, 120 + C = 180

Or, C = 180 120

Or, C = 60

Now,

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Alternate method

We know that sum of external angles of a polygon = 360

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Solution:

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We know that angle sum of a quadrilateral = 360

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Alternate method

We know that sum of external angles of a polygon = 360

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NCERT Solutions of Quadrilaterals Class 9
<< Solution of NCERT math Exercise 3.1 (Part 1)Solution of NCERT Exercise 3.2 >>

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