Answer:
AB
Step-by-step explanation:
You want an expression of the symmetric property of equality, given AB = CD.
Symmetric property
The symmetric property of equality says you can swap sides of the equal sign and the relation is still true:
AB = CD ⇔ CD = AB . . . . . symmetric property of equality
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Additional comment
This is different from the reflexive property, which states a quantity is equal to itself:
AB = AB . . . . . reflexive property of equality.
The symmetric property can be used to rearrange equations to a convenient form. For example, solving 3 = x +1, we can subtract 1 from both sides to get 2 = x. Often we like to write this with the variable name on the left side of the equal sign: x = 2. The symmetric property lets us do that.
