Which of these statements are true for joint variations? Check all that apply.

In a joint variation, one variable varies directly as the product of two or more other variables. It is written as y = kxz (or a similar equation), where k is the constant of proportionality, so statement B is true. Because joint variation involves at least two independent variables, statement C is also true. There is one constant of proportionality, not necessarily 1, so A and D are false.

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