Which equation describes this relationship? Remember to include k, the constant of variation. a varies directly with b and inversely with c and dChoices:\[[A]a = \frac{kb}{cd}\]\[[B]a = \frac{kbd}{c}\]\[[C]a = \frac{k}{bcd}\]\[[D]a = \frac{kd}{bc}\]
Q. Which equation describes this relationship? Remember to include k, the constant of variation. a varies directly with b and inversely with c and dChoices:\[[A]a = \frac{kb}{cd}\]\[[B]a = \frac{kbd}{c}\]\[[C]a = \frac{k}{bcd}\]\[[D]a = \frac{kd}{bc}\]
Identify direct variation: Identify the direct variation component of the relationship. Since a varies directly with b, the equation should start with a=kb, where k is the constant of variation.
Identify inverse variation: Identify the inverse variation component of the relationship. Since a varies inversely with c and d, this means that a should be divided by the product of c and d. The equation should incorporate cd1 to represent the inverse variation with c and d.
Combine direct and inverse variations: Combine the direct and inverse variations into one equation. Since a varies directly with b and inversely with c and d, the equation should multiply b by the constant of variation k and divide by the product of c and d. The combined equation is a=cdkb.
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