(Worth 50 points. Don't post your answer unless you have good ideas) Solve the following problem: Which triangles are similar ?

 ΔABC ≅ ΔADB

Step-by-step explanation:

In order to be similar, they must have the same angles.

    ΔABC                                  ΔADB                              ΔDBC

∠A = 180 - (2a + b)             ∠A = 180 - (2a + b)         ∠D = 180 - (a + b)

∠B = a + b                           ∠D = a + b                      ∠B = b

∠C = a                                 ∠B = a                            ∠C = a

ΔABC and ΔADB have the same angles so they are similar.

Each corresponding line has identical slopes.

Step-by-step explanation:

AB and EF

BC and FG

CD and GH

DA and HE