find the constant of variation for the relation and use it to write an equation for the statement. Then solve the equation.
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Answer:
k = ⅔
d. y = ⅔xz; y(6, 3) = 12
Step-by-step explanation:
y ∝ x and y ∝ z, so
y ∝ xz and
(1) y = kxz Divide each side by xz
k = y/(xz) Let x = 1, z =4, y = ⁸/₃
= (⁸/₃)/(1 × 4)
= ⁸/₃ × ¼ Cancel 4s
(2) k = ⅔ Substitute into (1)
y = ⅔xz Let x = 6, z = 3
y = ⅔ × 6 × 3 Cancel 3s
y = 2 × 6
y = 12
y(6, 3) = 12