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Parallel Lines

Coplanar lines that do not intersect.

Skew Lines

Lines that don't intersect and are not coplanar.

Transversal

A line that intersects two or more coplanar lines at different points.

Consecutive Interior Angles

Interior angles that lie on the same side of the transversal.

Alternate Interior Angles

Nonadjacent interior angles that lie on opposite sides of the transversal.

Alternate Exterior Angles

Nonadjacent exterior angles that lie on opposite sides of the transversal.

Corresponding Angles

Nonadjacent angles that lie on the same side of the transversal, where one angle is in the interior and the other on the exterior.

Slope

The ratio of change along the y-axis between any two point on a line.

Perpendicular Lines

Lines that intersect to form right angles.

Equidistant

The distance between two lines measured along a perpendicular to the lines is always the same.

Slope-intercept form

y= mx + b (where m= slope and b= the y-intercept)

Point-slope form

y- y1= m(x-x1)