Question

In quadrilateral ABCD, I(AB)=15 cm, I(AE)=6 cm ,I(BC)=8cm, I(CE)=21 cm . Find its area from the given measurements.
Options:
123 sq cm
120 sq cm
132 sq cm

Answer 1

The section is divided into two sub-parts:

1. Triangles as parts of rectangles

2. Generalising for other congruent parts of rectangles

Before moving onto exercise 11.2, the topics Area of triangle and parallelogram are discussed.  

Area of a square = side × side

Area of a rectangle = length × breadth

Area of a parallelogram = base × height

Area of a triangle =1/2 × base × height  

In the other half of the chapter, circles are explained. The topic is explained in two parts:

1. Circumference of Circle

The distance around a circular region is known as its circumference.  

Circumference of a circle = πd