In the diagram; 108^\circ + x + x = 180^\circ (sum of angle in a triangle) 108^\circ + 2x = 180^\circ x = 180^\circ - 108^\circ = 72^\circ x = \(\frac{72^o}{2}\) = 36^\circ (Angle between tangent and a chord through the point of contact) Hence, angle PTN = 90 + 36 = 126^\circ