Geometry help is much appreciated.

D) Definition of midpoint

Step-by-step explanation:

Triangle AXB and triangle BXC are congruent.Triangle AXB is a reflection of the triangle BXC.A congruent figure has the same shape and the same size. the point X divides the line AC into two equal parts.The distance from A to X and from C to X is the sameThis makes AX and AC equal making triangles BXA and BXC congruent.The midpoint X is the 4th proof in this answer

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