# If any one is having RD.Sharmas guid for class 9 pls let me know how to solve the 12th q -

1## Answers

Blades of a magnetic compass are forming a rhombus having all equal sides measuring 5cm each. A diagonal measuring 1 cm is given which is forming the triangular shapes of the blades of the magnetic compass and dividing the rhombus into 2 congruent triangles, say ABC and DBC having equal dmensions.

A= under root s(s-a)(s-b)(s-c), where

s= (a+b+c)÷2

therefore the area of triangle ABC,say A1 having sides 5cm, 5cm, 1cm is given by

a=5 cm

b=5 cm

c=1 cm.

hope dis helps u..!!!