Let, ABC be a triangle and base BC produced to both sides.
Exterior angles are ∠ABD and ∠ACE.
∠ABD = 104°
∠ACE = 136°
∠ABD + ∠ABC = 180°(Linear pair)
104° + ∠ABC = 180°
∠ABC = 180° – 104°
= 76°
∠ACE + ∠ACB = 180°
136° + ∠ACB = 180°
∠ACB = 180° – 136°
= 44°
In ΔABC
∠A + ∠ABC + ∠ACB = 180°
∠A + 76° + 44° = 180°
∠A + 120° = 180°
∠A = 180° – 120°
= 60°
Thus, angles of triangle are 60° , 76° and 44°.