Check sibling questions

To find area of any general quadrilateral,

We split it into triangles and add their area parallelogram has opposites sides equal & parallel

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For Quadrilateral ABCD

We join AC

Area of General Quadrilateral - Part 2

So, we have two triangles - Δ ADC and Δ ABC

Let h 1 be height from point D to AC 

   & h 2 be height from point B to AC

 

So,

Area of Quadrilateral ABCD

  = Area of Δ ADC + Area of Δ ABC

  = 1/2 × AC × h 1 + 1/2 × AC × h 2

  = 1/2 × AC × (h 1 + h 2 )

  = 1/2 × (h 1 + h 2 )

where d = Length of Diagonal

 

Find area of quadrilateral ABCD

Area of General Quadrilateral - Part 3

Given

Length of diagonal = d = 10 cm

Length of Perpendicular dropped on AC

         h 1 = 5 cm

     & h 2 = 3 cm

Now,

 Area of ABCD = d/2 (h 1 + h 2 )

   = 10/2 (5 + 3)

   = 10/2 × 8

     = 5 × 8

     = 40 cm 2

 

Area of quadrilateral = 40 cm 2

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Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 12 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.