Question

Find the area of a triangle, two sides of which are 18cm and 10 cm and the perimeter is 42 cm ​

Answer 1

Answer:

21√11 cm2

Step-by-step explanation:

Given

The length of the two sides is given as 18 cm and 10 cm respectively.

Perimeter = 42 cm.

Find out

We have to determine the area of a triangle

Formula

By using Heron’s formula, area of triangle= [latex]\sqrt{s(s-a)(s-b)(s-c)}[/latex]

Solution

Semi Perimeter (s) = (a+b+c)/2

s = (18+10+14)/2

s = 21 cm

ar(△ABC) = √s(s-a)(s-b)(s-c)

= √21(21-18)(21-10)(21-14)

= √21×(3)×(11)×(7)

= 21√11 cm2

Answer

Hence, the area of triangle is 21√11 cm2