Construction: Join OA, OB, OC, OE ⊥ AB at E and OF ⊥ AC at f
We know that tangent segments to a circle from the same external point are congruent Now, we have
AE = AF,BD = BE = 4 cm and CD = CF = 3 cm
Now,
∴ AB = 4 + 3.5 = 7.5 cm and AC = 3 + 3.5 = 6.5