Final answer:
The property of equality illustrated in the statement is the Multiplication Property of Equality.
Step-by-step explanation:
The property of equality that the statement If x=y, then 3x = 3y illustrates is the Multiplication Property of Equality. This property states that if you multiply both sides of an equation by the same non-zero number, the resulting equation is still true. In this case, multiplying both sides of x=y by 3 gives us 3x = 3y, which is still true since both sides of the equation are equal.
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