12 terms

parallel lines

lines in the same plane that never intersect

intersecting lines

lines that cross at exactly one point

perpendicular lines

Lines that intersect to form right angles

Congruent figure

Figures that have the same size and shape

Similar figure

figures that have the same shape but not necessarily the same size

line of symmetry

a line that divides a figure into two halves that are mirror images of each other

Rotational symmetry

If you can rotate an object less than 360 degrees and the object looks like it did before you turned it, then the object has rotational symmetry.

corresponding parts

Parts of congruent or similar figures that match.

line symmetry

If an object can have a line drawn down the center and both sides are congruent, then the object has line symmetry.

How to name a line segment?

Use the two endpoints of the line segment. Put a small straight line over the two letters ( no points needed)

How to name a ray?

Use two points on the Ray. The first one must be the endpoint, and the second could be any other point. Or if you only know the endpoint, use that. Over the letter or letters, draw a small line with an arrow on one end.

How to name a line?

Use two letters... one from each end of the diagram, nearest the arrows- draw a small line over the top of the letters, with arrows on both ends.