The AC side of triangle ABC lies in the alpha plane. Prove that the line passing through the midpoints of sides

The AC side of triangle ABC lies in the alpha plane. Prove that the line passing through the midpoints of sides AB and BC is parallel to the alpha plane.

If we draw through the midpoints of segments AB and BC, then this segment, passing through the midpoints of these two segments, will be the middle line of the triangle.
And the middle line, as we know, is parallel to one of the sides of the triangle, in this case, parallel to the AC side.
And since the AC side lies on the alpha plane, and the AC is parallel to the midline of the triangle, the alpha plane will be parallel to the midline of the ABC triangle, which is a straight line.