Advertisement Remove all ads

An isosceles triangle has perimeter 30 cm and each of the equal sides is 12 cm. Find the area of the triangle. - Mathematics

An isosceles triangle has perimeter 30 cm and each of the equal sides is 12 cm. Find the area of the triangle.

Advertisement Remove all ads

Solution

Let the third side of this triangle be x.

Perimeter of triangle = 30 cm

12 cm + 12 cm + x = 30 cm

x = 6 cm

`s="Perimeter of triangle"/2=30/2=15 cm`

By Heron's formula,

`"Area of triangle "=sqrt(s(s-a)(s-b)(s-c))`

                          `=[sqrt(15(15-12)(15-12)(15-6))]cm^2`

                          `=[sqrt(15(3)(3)(9))]`

                          `=9sqrt15 cm^2`

 

  Is there an error in this question or solution?
Advertisement Remove all ads

APPEARS IN

NCERT Class 9 Mathematics Textbook
Chapter 12 Heron's Formula
Exercise 12.1 | Q 6 | Page 203
Advertisement Remove all ads

Video TutorialsVIEW ALL [1]

Advertisement Remove all ads
Share
Notifications

View all notifications


      Forgot password?
View in app×