To solve a problem At isosceles triangles of ABC and CDE the general top of c, and the basis of CB and CD lie on one straight line Prove that straight lines of AB and DE are parallel

190
These triangles are equal on the first sign of equality of triangles (if two parties and a corner between nm of one treugolnics are respectively equal to 2 parties and a corner of other triangle, then such triangles are equal.) and as these triangles are equal and the bases at them are parallel that and storonyAV and DE are parallel.
117
Answer add