Acellus If this trapezoid is moved through the
translation (x-1, y+1), the coordinate of
A' will be:

a - base

b - exponent

so,

δabc ≅ δdcb by sas because

db ≅ ac . . given (side)

bc ≅ bc . . reflexive property (side)

∠dbc ≅ ∠ acb . . alternate interior angles where transversal bc crosses parallel lines bd and ac (included angle)