Question

Find the cost of levelling the ground in the form of triangle having sides 40m,70m and 90m at the rate of Rs 8 per.sq

Answer 1

By using Heron's formula ,

Area of triangle = √{s(s-a)(s-b)(s-c)}

where, s = (a+b+c)/2 where a,b,c are sides.

So, s = (40+90+70)/2 =100m

By putting the given values ,

Area = √{100(100-40)(100-90)(100-70)}

= √(100*60*10*30) = √(180000) = 300√2 m^2.