Home Geometry Problems All Problems 411-420 Post a comment         By Antonio Gutierrez
Problem 420. Triangle, Angles, Altitude, Sides, Measurement.
Level: High School, College, SAT Prep.

The figure shows a triangle ABC with BC = 3AB, altitude BD, angle DBC = 3 angle ABD, and AD = 1. Find CD.
 
 

Triangle, Angle, Altitude, Side, Measurement
 

 


 

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 ill-structured problem. By “construction,” we mean adding geometric figures (points, lines, planes) to a problem figure that wasn’t mentioned as "given."

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