Answer:
(-7 , 0)
Explanation:
When a point is reflected across the x-axis, presume it as the point is being mirrored on the left or right side. (7,0) is on the right side, and so to mirror it to the right we use the basis of the formula (-x,y). (x,y) is a point, and so to mirror it on the x-axis, we simply multiply the x value by -1. So in this case, (7 x -1, 0) = (-7 , 0)
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