eaakbari wrote:Mitch,
How did you conclude DE = BD = 1
All we did prior to that was drop a perpendicular.
When a problem indicates that an angle is 60 degrees, TRY TO DRAW A 30-60-90 triangle.
It is given that CD=2 and that ∠CDA= 60.
When CE is drawn perpendicular to AD, ∠CED=90, with the result that ∆CED is a 30-60-90 triangle.
In a 30-60-90 triangle, the sides are proportioned x : x√3 : 2x.
Since CD=2, the sides of ∆CED are DE=1, CE=√3, and CD=2.
It is given in the problem that BD=1.
Thus:
DE=BD=1.
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