A trapezium is a quadrilateral with one pair of opposite

sides parallel

So, in trapezium ABCD

    AB ∥ CD

4.jpg

 

Area of trapezium is

5.jpg

Area of trapezium = 1/2 × Sum of parallel sides × Height

              = 1/2 × (a + b) × h

 

Here,

Height is perpendicular distance between two parallel lines

 

Find area of trapezium

6.jpg

 

Here,

Parallel sides are 4 cm and 6 cm

and height is 3 cm

 

So, a = 4 cm, b = 6 cm and h = 3 cm

 

  Area of trapezium = 1/2 (a + b) × h

        = 1/2 × (6 + 4) × 3

        = 1/2 × 10 × 3

        = 5 × 3 = 15 cm 2

 

Find height of trapezium if parallel sides are 4 cm and 6 cm and area of trapezium is 15 cm 2

7.jpg

Here,

parallel sides are 4 cm and 6 cm

So, a = 4 cm, b = 4 cm

 

    Area of trapezium = 1/2 (a + b) × h

             15 = 1/2 × (6 + 4) × h

     15 = 1/2 × 10 × h

     15 = 5h

  15/5 = h

      h = 3 cm

 

  1. Chapter 11 Class 8 Mensuration
  2. Concept wise

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Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.