Q. 28. Prove that the ratio of the areas of two similar triangles is equal to the ratio of squares of their corresponding sides. Using the above result, prove the following :
If D is a point on the side AB of ΔABC such that
AD : DB = 3 : 2 and E is a point on BC such that
DE||AC; find the ratio of the areas of ΔABC and
ΔBDE.
Sol.
Part I : See Theorem 2, Page (xxxi).
Part II .
Or
Prove that the lengths of the two tangents drawn from an external point to a circle are equal. Using the above, do the following :
Two concentric circles are of radii 5 cm and 3 cm. Find the length of the chord of the larger circle which is tangent to the smaller circle.
Sol. Part I : See Theorem 6, Page (xxxii).
Part II.
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