9514 1404 393
Answer:
D. x = 5
Explanation:
Add x+3 to both sides and simplify.
9x -3 -8x +(x +3) = 7 -x +(x +3)
2x = 10 . . . . . simplify
x = 5 . . . . . . . divide by 2
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As you can see, the expression we chose to add (x+3) is the one that results in variable terms being separated from constant terms after simplification.