Question

If tan (A+B-C) = 1 and sec (B+C-A) = 2, then angle A.​

Answer 1

Answer:

answer is 60

Step-by-step explanation:

Given,

--------(1),

Also, given,

--------(2),

Equation (1) + Equation (2),

2 B = 105 ⇒ B = 52.5

Now, triangle ABC is a triangle,

Where, A, B and C are the interior angles of the triangle ABC,

⇒ A + B + C = 180

⇒ A + B = 180 - C -------(3),

From equation (1) and (3),

180 - C - C = 45

⇒ 180 - 45 = 2∠C ⇒ C = 67.5

Now, from equation (3),

We will get,

A + 52.5 = 180 - 67.5

⇒ A = 60