9x - 9y = -45
9y - 9x = 45 multiply this by -1
9x - 9y = -45
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9x = -45 + 9y
9y = 9x + 45
y = x + 5
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9y - 9x = 45
9y = 9x + 45
y = x + 5
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the lines are the same therefore the order pair is all real number in the domain and range.