Which method can be used to show that abc must be similar to edc?

To show that triangle ( abc ) is similar to triangle ( edc ), you can use the Angle-Angle (AA) similarity criterion. If you can establish that two angles in triangle ( abc ) are congruent to two angles in triangle ( edc ), then by AA similarity, the triangles are similar. This method relies on the fact that if two angles of one triangle are equal to two angles of another triangle, the corresponding sides will be in proportion, confirming similarity.