When a triangle is formed inside a semicircle, two lines from either side of the diameter meet at a point on the circumference at a right angle. The angle in a semicircle is a right angle of \(90 ...

The angle on a straight line is 180°. The angle VOY = 180°. The angle at the centre is double the angle at the circumference. Angle VWY = \(\frac{1}{2}\) of angle VOY = \(\frac{1}{2} ...