Problem 688: Triangle, Angles, 10, 20, 30, 40, 60 Degrees, Measure,
Mind Map, Polya.
Level: High School, College, SAT Prep.
The drawing shows a triangle ABC with points E and D on AB and
AC, respectively. If the measure of the angles BAC, ACE, BCE,
and ABD are 20, 30, 10, and 60 degrees, respectively, find the measure of
angle BDE.
Geometry problem solving
Geometry problem solving is one of the most
challenging skills for students to learn. When a
problem requires auxiliary construction, the
difficulty of the problem increases drastically,
perhaps because deciding which construction to
make is an illstructured problem. By
“construction,” we mean adding geometric figures
(points, lines, planes) to a problem figure that
wasn’t mentioned as "given."
How to Solve It, Interactive Mind Map
George Pólya's 1945 book "How to Solve It, A new
aspect of Mathematical Method", is a book
describing methods of problem solving. It
suggests the following steps when solving a
mathematical problem: (1) First, you have to
understand the problem. (2) After understanding,
then make a plan. (3) Carry out the plan. (4)
Look back on your work. How could it be better? Mind Map Help. To see a note: Hover over a yellow note button. To Fold/Unfold: click a branch. To Pan: click and drag the map canvas.

Recent Additions
