Angle Relationships

Adjacent Angles 1.Are “next to” each other 2.Share a common side C D are adjacent K J are not adjacent - they do not share a side

Vertical Angles 1.Are across from each other when two lines intersect 2.Are Congruent There are two pairs of vertical angles: What appears to be true about these two pairs of angles? We show that by using “tick marks” over the arcs

Complementary Angles -Two angles whose sum is 90° A B are complementary M N If the measure of is 37°, what is m ? is 53° Angles M and N are complementary.

Supplementary Angles -Two angles whose sum is 180° AB are supplementary M N If the measure of is 152°, what is m ? is 28° Angles M and N are supplementary.

Perpendicular Lines Two lines are perpendicular if they intersect at 90° angles m n Are these two lines ? No

Parallel Lines 1.Do not intersect 2.Lie in the same plane k m Are these lines parallel? No; they would intersect if they both continued

Transversal A line that “cuts through” two or more other lines (usually the other two are parallel) Which line is the transversal?

Corresponding Angles When a transversal cuts through two parallel lines, it creates 4 sets of corresponding angles. Corresponding angles are angles that are in the same position when a transversal cuts two parallel lines If I could cut out a whole where this rectangle is, and move it down, each angle would line up with its corresponding angle exactly. Therefore, corresponding angles are congruent.

Skew Lines 1.Lines that do not intersect 2.Do not lie in the same plane Lines and are skew Lines and are not skew; they are parallel. They lie in the same plane.

Apply what you know Find the measures of the seven missing angles. 125°