# NCERT Class 9 Solutions: Heron՚s Formula (Chapter 12) Exercise 12.2 Part 1 (For CBSE, ICSE, IAS, NET, NRA 2022)

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Q-1 A park, in the shape of a quadrilateral ABCD, has . How much area does it occupy?

Solution:

Given a quadrilateral ABCD with, .

To find the area of quadrilateral we can add the areas of two trianlges. In , by applying Pythagoras theorem,

Also since triangle is right triangle, Area of Now, semi perimeter of

Using heron՚s formula, area of

• (approx.)

Q-2 Find the area of a quadrilateral ABCD in which

Solution:

We can calculate the area of the two triangles by using heroes՚ formula on the two triangles. However we can make things simple by first proving that that is a right triangle. let՚s see if it satisfies Pythagoras theorem,

Thus, is a right angled at C. Area of

Now, semi perimeter of

Using heron՚s formula, area of

• (approx.)