2. Axisymmetric figure: mathematical term, defined as a figure folded along a straight line in a plane, and the parts on both sides of the straight line can completely overlap;
3. The straight line is called the symmetry axis, and the symmetry axis is represented by the dotted line;
4. The symmetry axis is a straight line;
5. In an axisymmetric figure, the distance between the corresponding points on both sides of the axis of symmetry is equal;
6. Axisymmetric graphics, folded in half along the axis of symmetry, completely overlapping left and right;
7. If two figures are symmetrical about a straight line, then this straight line is the line segment whose symmetry axis bisects the symmetry point vertically;
8. Graphic symmetry.