Tangential Quadrilateral - Angle Formulas

Angle Formulas

If e, f, g and h are the tangent lengths from the vertices A, B, C and D respectively to the points where the incircle is tangent to the sides of a tangential quadrilateral ABCD, then the angles of the quadrilateral can be calculated from

The angle between the tangency chords k and l is given by

Read more about this topic:  Tangential Quadrilateral

Famous quotes containing the words angle and/or formulas:

    The good lawyer is not the man who has an eye to every side and angle of contingency, and qualifies all his qualifications, but who throws himself on your part so heartily, that he can get you out of a scrape.
    Ralph Waldo Emerson (1803–1882)

    It is sentimentalism to assume that the teaching of life can always be fitted to the child’s interests, just as it is empty formalism to force the child to parrot the formulas of adult society. Interests can be created and stimulated.
    Jerome S. Bruner (20th century)