Explanation:
Draw a circle.
Find it's center.
From the center divide the circle into four equal parts, by drawing two diameters , such that angle between two diameter is a right angle.
As, circle is divided into four equal parts, and each part is equivalent to [tex]\frac{1}{4}[/tex].
So, measure of each part in terms of angles in degrees can be found as
[tex]\frac{1}{4}\times 360=90 {\text{degree}}[/tex]
the reason is measure of complete circle is 360 degree.
