[tex]3(d - 7) = 6 \\ \\ = > 3d - 21 = 6 \\ \\ = > 3d = 6 + 21 \\ \\ = > 3d = 27 \\ \\ = > d = \cancel \frac{27}{3} \\ \\ = > d = 9[/tex]
Answer:
D = 9
Step-by-step explanation:
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