The sum of the interior angles of a polygon is 20 right angles. How many sides does the polygon have?

In the figure above, PQR is a straight line segment, PQ = QT . Triangle PQT is an isosceles triangle. $\angle QPT$is 25^o . Calculate the value of $\angle RST$

Find the number of sides a regular polygon whose interior angle is twice the exterior angle

An equilateral triangle of sides $\sqrt{3}$is inscribed in a circle. Find the radius of the circle.

In a regular polygon, each interior angle doubles its corresponding exterior angle. Find the number of sides of the polygon.