The areas of two similar triangles are 81 cm2 and 49 cm2 respectively. If the altitude of the bigger triangle is 9 cm, find the corresponding altitude of the smaller triangle.
3.5 cm
4.5 cm
6 cm
7 cm
The ratio of the areas of two similar triangles is equal to the ratio of the squares of their corresponding altitudes.
Let two similar triangles be ABC and DEF