Answer: BC is not a tangent line because m∠ABC≠90°.
Step-by-step explanation:
From the given picture, we have given a triangle ΔABC, in which
∠A=25° and ∠C=60°, AB is the radius of the circle.
if BC is tangent to circle then ∠B must equals to 90°because tangent line makes right angle with the radius of the circle.
Since, we know that by angle sum property of a triangle , the sum of all angles of triangle is 180°.
Therefore, in ΔABC
∠A+∠B+∠C=180°
⇒∠B=180°-∠A-∠C
⇒∠B=180°-25° -60°
⇒ ∠B=95°≠90°
⇒ BC is not tangent line .
