Obtuse angle – GeoGebra

Is 9.6in, 20.1in, and 18in an acute, obtuse, or a right angle? - Quora

obtuse triangle – GeoGebra

Given: obtuse triangle ABC with obtuse angle B. Point D on side AC such that angle BDC is also obtuse. Angle DAB is 2/3 of angle ABD. Angle BCD is 1/5 angle

exzuberant: Really, really understanding the area of a triangle (Part 2)

Lines and Angles – GeoGebra

Textbooks :: Mathspace

exzuberant: Really, really understanding the area of a triangle (Part 2)

Exterior Angle of a Triangle – GeoGebra

Simple Angles Review – GeoGebra

IGS, Dynamic Geometry 1471: Equilateral Triangle, Inside/Outside Point, Incenters, Tangency Points, Concurrent Lines, Step-by-step Illustration, GeoGebra, iPad Apps. Typography

Learn Geogebra - Open Educational Resources

Obtuse angle – GeoGebra

Obtuse angles and the unit circle. – GeoGebra