3.1 Lines and Angles
Parallel lines: coplanar lines that do not intersect.
Perpendicular lines: lines that intersect at 90 degrees
Skew lines: not parallel, not coplanar, and do not intersect
Parallel planes: planes that do not intersect
Transversal: a line that intersects two coplanar lines at two different points
Corresponding angles: angles that lie on the same side of the transversal and on the same sides of the two lines
Alternate interior angles: nonadjacent angles that lie on opposite sides of the transversal and between the two lines
Alternate exterior angles: lie on opposite sides of the transversal, and on the outsides of the two lines
Same-side interior angles: lie on the same side of the transversal and between the two lines
Perpendicular lines: lines that intersect at 90 degrees
Skew lines: not parallel, not coplanar, and do not intersect
Parallel planes: planes that do not intersect
Transversal: a line that intersects two coplanar lines at two different points
Corresponding angles: angles that lie on the same side of the transversal and on the same sides of the two lines
Alternate interior angles: nonadjacent angles that lie on opposite sides of the transversal and between the two lines
Alternate exterior angles: lie on opposite sides of the transversal, and on the outsides of the two lines
Same-side interior angles: lie on the same side of the transversal and between the two lines