From the figure,
Now it can be seen that both the triangles are similar as the corresponding sides are propotional.
From the figure we can see that,
∠ P = ∠ C
From ΔABC,
∠ A + ∠ B + ∠ C = 180°
60° + 80° + ∠ C = 180°
∠ C = 180° – 140°
∠ C = 40°
Hence, ∠ P = 40°