Question

For the trapezium , find its area.

• A. $146.64sq.cm$
• B. $176.64sq.cm$
• C. $196.64sq.cm$
  
• D. $116.64sq.cm$
  

Answer 1

The correct option is A $146.64sq.cm$

Given $AB=20$ cm ,$DC=12$ cm And $AD=CD=10$ cm

Then Diff of AB and $DC=20-12=8$ cm

Then height of figure =$\sqrt{(10{)}^2-(4{)}^2}=\sqrt{100-16}=\sqrt{84}=2\sqrt{21}$

So area of figure$=2\sqrt{21}\left(\frac{20+12}{2}\right)=2\sqrt{21}\times 16=32\sqrt{21}=146.64c{m}^2$