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meow18
When solving the system x + 2y = 9 and x - y = 6, which expression could be substituted for x in the second equation? A. 9 - x B. y - 9/2 C. 9 - 2y D. 1/2 y + 9
well first you have to get x to equal something in the first equation, we can do that by subtracting 2y from both sides to get the x alone. it should look like x=9-2y so C is your answer