Question

find the cost of levelling a ground in the form of triangle sides 16m,12,m,and 20m at rs 4 per sq.meter

Answer 1

Let the sides be
a=16,b=12,c=20. (By herons formula)
s = a+b+c = 16+12+20. 48
----------. -------------- =. ----- =. 24
2. 2. 2

A = √s(s-a)(s-b)(s-c)
A = √24(24-16)(24-12)(24-20)
A = √24×8×12×4
A = √(2×2×3×2)(2×2×2)(2×3×2)(2×2)
A = 2×2×2×2×2×3
A = 96 m sq.
Cost per metre=4
Cost for 96 m = 4×96
=384 rs

Answer 2

Answer:

Step-by-step explanation:

Let sides of a triangle be a =51 m, b=37 m and c =20 m

Now, semi-perimeter of triangle.

s=a+b+c/2

=51+37+20/2=1082/2

=54 m

∴ Area of triangle=s(s−a)(s−b)(s−c)−−−−−−−−−−−−−−−−−√ [by Heron's formula]

=54(54−51)(54−37)(54−20)−−−−−−−−−−−−−−−−−−−−−−−−√

=54×3×17×34−−−−−−−−−−−−−√

=9×3×2×3×17×17×2−−−−−−−−−−−−−−−−−−−−−−√

=3×3×2×17

=306 m^2

∵cost of leveling per m^2

=rupee 3

∴cost of leveling per 306 m^2

=3×306

=918 Rs