Question

In a triangle ABC, if <A + <C = 140° and <A + 3 < B = 180°, then <A is equal to​

Answer 1

Answer:

∠A = 60°

Step-by-step explanation:

We know that,

∠A + ∠B + ∠C = 180°

⇒ ∠A + ∠C = 180 - ∠B   →1

Given,

    ∠A + ∠C = 140            →2

Equating eqn. 1 and 2,

180 - ∠B = 140

- ∠B = 140 - 180

⇒ ∠B = 40°

   ∠A + 3∠B = 180

∠A + 3 × 40 = 180

    ∠A + 120 = 180

    ∴   ∠A = 60°

Have a nice day <3