Project: Circumscribed Triangle Radius Problem

The triangle in the figure below is circumscribed by a circle with radius r.


Find the value of r.


Any triangle can be circumscribed by a circle.

Find a formula for the radius of the circle, given the three sides of the triangle.

Show that, if you haven’t already done so, that r=\frac{a}{2sinA}.

Find a similar expression for r using angle B and side b; then angle C and side c. Hence prove the sine rule.

Done here! Take me back to the triangles menu.