In Fig. 10.68, a is drawn to circumscribe a circle of radius 4 cm such that the segments BD and DC are of lengths 8 cm and 6 cm respectively. Find the lengths of sides AB and AC, when area of is 84 cm2.


Firstly consider that the given circle will touch the given circle will touch the sides AB and AC of the triangle at a point E and F respectively.


Let AF=x


Now in triangle ABC


CF = CD=6cm


(Tangent drawn from an external point to a circle are equal. Here tangent is drawn from external point C)


BE = BD =8cm (Tangent drawn from an external point to a circle are equal. Here tangent is drawn from external point B)


AE = AF =X


Now AB= AE + EB =x + 8


Also BC = BD+ DC = 8+6 =14 and CA= CF+FA = 6+ x


Now we get all side of the triangle and its area can be find by using hero’s formula



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