3.1 Identify Pairs of Lines and Angles

Parallel Lines Have the same slope Can be contained in the same plane Are everywhere the same distance apart

Parallel

Skew Lines Non intersecting Non parallel Can not be contained in the same plane

Skew

Perpendicular

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

Postulates If there is a line and a point not on the line, then there is exactly one line through the point that will be parallel to the line If there is a line and a point not on the line, then there is exactly one line through the point that will be perpendicular to the line

Angle Positions Relative to Two Lines

Angles formed by transversals Alternate interior Alternate exterior Corresponding Consecuitive

Alternate interior angles = lie between the lines on opposite sides of the transversal Alternate Exterior = lie outside the lines on opposite sides of the transversal Corresponding = angles having corresponding positions Consecutive = lie between the lines on the same side of the transversal

Alternate Interior Angles

Alternate Exterior Angles

Consecutive Angles

Corresponding Angles