Asequence of transformations maps ∆abc onto ∆a″b″c″. the type of transformation that maps ∆abc onto ∆a′b′c′ is a

when ∆a′b′c′ is reflected across the line x = -2 to form ∆a″b″c″, vertex
of ∆a″b″c″ will have the same coordinates as b′.

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