Which angle In ABC has the largest measure ?
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The angle with the largest measure is opposite the longest side. The longest side is 12. It is opposite angle B. The appropriate choice is ...
B. ∠B
Answer:
Option B. ∠B
Step-by-step explanation:
In this question three sides of a triangle are given as AB = 10, BC = 10, AC = 12
and we have to tell the largest angle of the triangle.
As per sine rule we know
sin A/BC = sin B/ AC = sin C/ AB
Here sin A/10 = sin C/10
⇒sin A = sin C
therefore ∠A = ∠C
(sin B)/12 = (sin C)/10
⇒ sin B/ sin C = 12/10 = 1.2 : 1
Therefore ∠B:∠C :: 1.2 : 1
similarly ∠B:∠A :: 1.2 : 1
Therefore ∠B is the largest angle.