SOLUTION: In Triangle ABC, AD is a median. Prove that AB^2 + AC^2 = 2AD^2 + 2DC^2.

Question 208755: In Triangle ABC, AD is a median.
Prove that AB^2 + AC^2 = 2AD^2 + 2DC^2.
Answer by Edwin McCravy(20055) (Show Source): You can put this solution on YOUR website!
In Triangle ABC, AD is a median.
Prove that AB^2 + AC^2 = 2AD^2 + 2DC^2.




 by the Pythagorean theorem

 by the Pythagorean theorem

 because equals 
                 added to equals 
                 give equals.

 because Median AD bisects side BC

  Substituting DC for BD

   Combining like terms.

Edwin

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