Question

find Area of triangular park
Whose two Bide are 18cm and
10cm. fare Perimetey is 42cm.
find the cost of force at the
rate
of
5 paise/cm​

Answer 1

Given,
Side a=18cm
Side b=10cm
Perimeter=42cm=a+b+c
:. Putting value
42=18+10+c
42=28+c
42-28=c
14=c
Now,
S=(a+b+c)/2
:. Putting value
S=42/2
S=21
Now according to Heron's formula-
Area of a triangle
=√{s(s-a)(s-b)(s-c)}
:. Putting value
=√{21(21-18)(21-10)(21-14)}
=√{21(3)(11)(7)}
=√4851
=21√11cm²



Please mark as brainiest answer

Answer 2

Answer:

$\large\mathbb\color{purple}\underline{\underline{Question:}}$

$\textsf{Find the area of the triangular park. Whose}$

$\textsf{two sides are 18 cm and 10 cm.The}$

$\textsf{perimeter is 42 cm.Find the cost of}$

$\textsf{fence at the rate of 5 paise / cm .}$

$\large\mathbb\color{orange}\underline{\underline{Given:}}$

$\textsf{Height of the triangle = 18 cm}$

$\textsf{One side of the triangle = 10 cm}$

$\textsf{Perimeter of the triangle = 42 cm}$

$\textsf{Cost of the fence per cm = 5 paise}$

$\large\mathbb\color{red}\underline{\underline{To\:find:}}$

$\textsf{(i) Area of the triangle}$

$\textsf{(ii) Cost of the fence of the triangular park}$

$\large\mathbb\color{cyan}\underline{\underline{Taken:}}$

$\bold\green{Base=P-(H+S)}$

$\bold{Where,}$

$\bold{P=Perimeter\:of\:the\:triangle}$

$\bold{H=Height\:of\:the\:triangle}$

$\bold{S=Side\:of\:the\:triangle}$

$\bold\green{Area=\frac{H×B}{2}}$

$\bold{Where,}$

$\bold{B=Base\:of\:the\:triangle}$

$\bold{B=Base\:of\:the\:triangle}$

$\bold\green{Cost\:of\:the\:fence=P×Cost\:per\:cm}$

$\large\mathbb\color{magenta}\underline{\underline{Concept:}}$

$\textsf{First find the base of the triangle then find the area.}$

$\textsf{At last find the cost of the fence.}$

$\large\mathbb\color{blue}\underline{\underline{Solution:}}$

$\bold\purple{Base:}$

$\bold{Taken,Base=P-(H+S)}$

$\bold{Base=42cm-(18cm+10cm)}$

$\bold{Base=42cm-28cm}$

$\bold{Base=20cm}$

$\bold\purple{Now,find\:the\:area}$

$\bold{Taken,Area=\frac{H×B}{2}}$

$\bold{Area=\frac{18cm×20cm}{2}}$

$\bold{Area=\frac{360cm}{2}}$

$\therefore\boxed{\red{Area=180cm}}$

_________________________________

$\bold\purple{Cost\:of\:the\:fence:}$

$\bold{Taken,Cost\:of\:the\:fence=P×Cost\:per\:cm}$

$\bold{Cost\:of\:the\:fence=42cm×5p/cm}$

$\therefore\boxed{\red{Cost\:of\:the\:fence=210p\:or\:2\:rs\:10\:p}}$

_________________________________

So , the area of the triangle is 180 cm .

And the cost of the fence of triangular park is ₹2.10 .

HOPE IT HELPS YOU