NCERT Class 9 Solutions: Heron՚s Formula (Chapter 12) Exercise 12.1 Part 2 (For CBSE, ICSE, IAS, NET, NRA 2022)

Get unlimited access to the best preparation resource for CBSE/Class-9 : get questions, notes, tests, video lectures and more- for all subjects of CBSE/Class-9.

Herons Formula and Its Components

Q-5 Sides of a triangle are in the ratio of and its perimeter is . Find its area. Solution:

  • Ratio of the sides of the triangle
  • Let the common ratio be then sides are
  • Perimeter of the triangle
    • ()
  • Sides of triangle are,
    • ()
    • ()
    • ()
  • Semi perimeter of triangle (s)

Using heron՚s formula, area of the triangle

Q-6 An isosceles triangle has perimeter 30 cm and each of the equal sides is 12 cm. Find the area of the triangle. Solution:

  • Length of the equal sides
  • Perimeter of the triangle
  • Length of the third side
  • Semi perimeter of the triangle (s)
  • Using heron՚s formula, area of the triangle

Developed by: