Respuesta :

Answer:

The top angle of the triangle is, X = 68°.

Step-by-step explanation:

Let there is a triangle named PQR with bottom corner angles ∠ P and ∠ Q and the ∠ R is the angle at the top.

Now, given that ∠ P = 31° and ∠ Q = 81° and we have to find out ∠ R i.e. X.

In Δ PQR, we know, ∠ P + ∠ Q + ∠ R = 180°

⇒ 31° + 81° + X = 180°

X = 68°

Therefore, the top angle of the triangle is 68°. (Answer)