Consider the regular octagon below with a center at the organ and a vertex at 4,0

Reflection on y=0
Step-by-step explanation:
The property to note when a point is reflected on the line y=0 is that the object figure will be congruent to the image figure.Here the distance of the object from the axis of reflection will equal that distance of image from the axis of reflection.In this case, the object point (0,-4) will reflect at (0,-4). The same will occur for object point (0,4) which will reflect at (0,-4). Doing the same for all the points, the image formed will be carried onto the polygon itself.
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Reflection of objects along x-axis :https://brainly.com/question/5017530
Keywords: octagon, reflection, vertex
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Answer:
B. Reflection across line y = 0
Step-by-step explanation:
Reflection across line y = 0 is equivalent to reflection over x-axis, which transforms point (x, y) into (x, -y).
The coordinates of the octagon are:
(-4, 0)
(-2.9, 2.9)
(0, 4)
(2.9, 2.9)
(4, 0)
(2.9, -2.9)
(0, -4)
(-2.9, -2.9)
which are transformed into:
(-4, 0) -> (-4, 0)
(-2.9, 2.9) -> (-2.9, -2.9)
(0, 4) -> (0, -4)
(2.9, 2.9) -> (2.9, -2.9)
(4, 0) -> (4, 0)
(2.9, -2.9) -> (2.9, 2.9)
(0, -4) -> (0, 4)
(-2.9, -2.9) -> (-2.9, 2.9)
which coincided with the original octagon