Solution
In the diagram,
∠DCE = ∠ACB = 60 (vertically opposite angle are equal)
∠ABC = ∠CDE = 72 (alternate angle are equal)
∠BAC + ∠ACB + ∠CBA = 180
=> ∠BAC = 180 - ∠ACB - ∠CBA = 180 - 60 - 72 = 48
Also, ∠CED = ∠BAC = 48
SInce ∠A = ∠D, ∠B = ∠E and ∠C = ∠C
Hence △ABC is similar to △DEC