Thread: isosceles triangle

In the isosceles triangles ABC and CDE below, BC = 16 in., DE = 11 in. What is CD - AD?

Here

Hello, sanee66!

In the isosceles triangles and below,
. .
What is ?

Code:

            A
            *
           *   *  D       11
          *       *   *   *   *   * E
         *           *           *
        *               *       *
       *                   *   *
    B *   *   *   *   *   *   * C
                 16

We have: .
. . . .and: .

Hence: .

Therefore: .