Answer: (B) Parallel to x-axis
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Step-by-step explanation:
Every point on the line y = 7 has a y coordinate of 7. Two such points are (0,7) and (1,7). The x coordinate can be anything you want. This line is completely horizontal and parallel to the x axis.
We can think of y = 7 as y = 0x+7. It's of the form y = mx+b with m = 0 as the slope and b = 7 as the y intercept.