Question:
In ∆ABC, ∠C = ∠A, BC = 4 cm and AC = 5 cm. Then, AB = ?
(a) 4 cm
(b) 5 cm
(c) 8 cm
(d) 2.5 cm
Solution:
Given: In ∆ABC, ∠C = ∠A, BC = 4 cm and AC = 5 cm.
In ∆ABC,
As, ∠C = ∠A (Given)
Therefore, $B C=A B$ (Sides opposite to equal angles.)
$\Rightarrow B C=A B=4 \mathrm{~cm}$
Hence, the correct option is (a).