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8-3. Angle Relationships. Course 2. Insert Lesson Title Here. Vocabulary. perpendicular lines parallel lines skew lines adjacent angles vertical angles transversal corresponding angles. 8-3. Angle Relationships. Course 2.
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8-3 Angle Relationships Course 2 Insert Lesson Title Here Vocabulary perpendicular lines parallel lines skew lines adjacent angles vertical angles transversal corresponding angles
8-3 Angle Relationships Course 2 When lines, segments, or rays intersect, they form angles. If the angles formed by two intersecting lines are equal to 90°, the lines are perpendicular lines. Some lines in the same plane do not intersect at all. These lines are parallel lines. Segments and rays that are part of parallel lines are also parallel. Skew lines do not intersect, and yet they are also not parallel. They lie in different planes.
8-3 Angle Relationships Reading Math The symbol means “is parallel to.” The symbol means “is perpendicular to.” Course 2
8-3 Angle Relationships UV and YV UV YV Course 2 Additional Example 1A: Identifying Parallel, Perpendicular, and Skew Lines Tell whether the lines appear parallel, perpendicular, or skew. The lines appear to intersect to form right angles.
8-3 Angle Relationships XU and WZ XU and WZ are skew. Course 2 Additional Example 1B: Identifying Parallel, Perpendicular, and Skew Lines Tell whether the lines appear parallel, perpendicular, or skew. The lines are in different planes and do not intersect.
8-3 Angle Relationships XY and WZ XY || WZ Course 2 Additional Example 1C: Identifying Parallel, Perpendicular, and Skew Lines Tell whether the lines appear parallel, perpendicular, or skew. The lines are in the same plane and do not intersect.
8-3 Angle Relationships WX and XU WX XU Course 2 Check It Out: Example 1A Tell whether the lines appear parallel, perpendicular, or skew. The lines appear to intersect to form right angles.
8-3 Angle Relationships WX and UV WX and UV are skew Course 2 Check It Out: Example 1B Tell whether the lines appear parallel, perpendicular, or skew. The lines are in different planes and do not intersect.
8-3 Angle Relationships WX and ZY WX || ZY Course 2 Check It Out: Example 1C Tell whether the lines appear parallel, perpendicular, or skew. The lines are in the same plane and do not intersect.
8-3 Angle Relationships Vertical angles are the opposite angles formed by two intersecting lines. When two lines intersect, two pairs of vertical angles are formed. Vertical angles have the same measure, so they are congruent. Course 2 Adjacent angles have a common vertex and a common side, but no common interior points. Angles 2 and 3 in the diagram are adjacent. Adjacent angles formed by two intersecting lines are supplementary
8-3 Angle Relationships Course 2 Reading Math Angles with the same number of tick marks are congruent. The tick marks are placed in the arcs drawn inside the angles.
8-3 Angle Relationships Course 2 A transversalis a line that intersects two or more lines. Line t is a transversal. When the lines that are intersected are parallel, four pairs of corresponding angles are formed. Corresponding angles are on the same side of the transversal and are both above or both below the parallel lines. Angles 1 and 5 are corresponding angles. Corresponding angles are congruent.
8-3 Angle Relationships Course 2 Additional Example 2A: Using Angle Relationships to Find Angle Measures Line n line p. Find the measure of the angle. 2 2 and the 130° angle are vertical angles. Since vertical angles are congruent, m2 = 130°.
8-3 Angle Relationships Course 2 Additional Example 2B: Using Angle Relationships to Find Angle Measures Line n line p. Find the measure of the angle. 3 3 and the 50° angle are acute angles. Since all of the acute angles in the figure are congruent, m3 = 50°.
8-3 Angle Relationships Course 2 Additional Example 2C: Using Angle Relationships to Find Angle Measures Line n line p. Find the measure of the angle. 4 4 is an obtuse angle. Since all of the obtuse angles in the figure are congruent, m4 = 130°.
8-3 Angle Relationships Course 2 Check It Out: Example 2A Line n line p. Find the measure of the angle. 45° 4 5 6 2 3 135° 7 n p 3 3 and the 45° angle are vertical angles. Since vertical angles are congruent, m3 = 45°.
8-3 Angle Relationships Course 2 Check It Out: Example 2B Line n line p. Find the measure of the angle. 45° 4 5 6 2 3 135° 7 n p 6 6 and the 135° angle are obtuse angles. Since vertical angles are congruent, m6 = 135°.
8-3 Angle Relationships Course 2 Check It Out: Example 2C Line n line p. Find the measure of the angle. 45° 4 5 6 2 3 135° 7 4 n p 4 is an obtuse angle. m4 + 45° = 180° In the figure, the acute and obtuse angles are supplementary. –45° –45° Subtract 45° to isolate m4. m4 = 135°
8-3 Angle Relationships Course 2 Insert Lesson Title Here Lesson Quiz Tell whether the lines appear parallel, perpendicular, or skew. 1.AB and CD 2.EF and FH 3.AB and CG 4. parallel perpendicular skew In Exercise 28, line r line 5. Find the measure of 4, 5, and 6. 55°, 125°, 125°