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Find the area of a quadrilateral ABCD in which `A B=3 c m , B C=4 c m , C D=4 c m , D A=5 c m a n d A C=5 c m`. |
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Answer» We can create a diagram with the given details. Please refer to video for the diagram. Now, in `Delta ABC`,`5^2 = 3^2+4^2` that means it is a right angle triangle as it is satisfying Pythagoras theorem. So, `ar(ABC) = 1/2**3**4 = 6cm^2` Now, in `Delta ACD`, `a=4cm,b=5cm and c = 5cm` So, Semi-perimeter,`s = (a+b+c)/2 = 14/2 = 7cm` So, `ar(ACD) = sqrt(s(s-a)(s-b)(s-c)) = sqrt(7**3**2**2)=2sqrt21cm^2` Thus, `ar(ABCD) = ar(ABC)+ar(ACD) = 6+2sqrt21cm^2` |
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