To match the number with the opposite, we are flipping the sign. If the sign is originally a negative, it would become a positive, and vice versa.
Term: 3.2 Match (Opposite): B) - 3.2
Term: -2.3 Match (Opposite): D) 2.3
Term: -1.5 Match (Opposite): C) 1.5
Term: 5.1 Match (Opposite): A) -5.1
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