The answer is C. One Solution (1, 5.5)
To make sure plug in the number
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y = (-1/2) (-1) + 5
5.5 = 0.5 + 5
TRUE for this equation
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y = (1/2) (-1) + 6
5.5 = -0.5 + 6
TRUE for this equation
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So for sure C. One Solution (1, 5.5) is your answer