Sides of two similar triangles are in the ratio 4 : 9. Areas of these triangles are in the ratio
(a) 2 : 3 (b) 4 : 9
(c) 81 : 16 (d) 16 : 81.
We know that the ratio of the areas of two similar triangles is equal to the ratio of the squares of any two corresponding sides.
Therefore,
Ratio of the areas of these triangles
= 42 : 92 = 16 : 81
Hence, (d) 16:81 is the correct option.
In the given fig, ABD is a triangle right angled at A and AC ⊥ BD. Show that
(i) AB2 = BC .BD
(ii) AC2 = BC. DC
(iii) AD2 = BD . CD