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Answer:
2/3
Step-by-step explanation:
You find each ratio x/y:
[tex]\frac{3}{2} = \frac{3}{2}\\\\\frac{6}{4} = \frac{3\cdot2}{2\cdot2} = \frac{3}{2}\\\\\frac{9}{6} = \frac{3\cdot3}{2\cdot3} = \frac{3}{2}[/tex]\
Therefore the constant is 3/2.