by herons formula calculate the area of shaded portion
Answers
Hey there mate!
Area of shaded portion=area of small triangle - area of large triangle.
Area of small triangle= semi-perimeter (s) = (a+b+c)/2
= (60+61+11)/2
= 66 meters
Therefore,
Area = sq.rt{s(s-a)(s-b)(s-c)}
= sq.rt{66(66-60)(66-61)(66-11)}
= sq.rt(66)(6)(5)(55) )
= sq.rt(2*3*11*2*3*5*11*5)
= 2*3*11*5
= 330 meter square
Area of big triangle= semi-perimeter (s) = (a+b+c)/2
= (120+122+22)/2
= 132 meter
Area = sq.rt(s(s-a)(s-b)(s-c) )
= sq.rt(132(132-120)(132-122)(132-22) )
= sq.rt(132(12)(10)(110) )
= sq.rt(2*2*3*11*2*3*2*5*2*2*5*11)
= 1320 meter square
Therefore,
Area of shaded portion = 1320 - 330
= 990 meter square