Honors Geometry; 10/8

We worked through the final two reasons of how to prove lines parallel today by showing how to use perpendicular lines and a third parallel line.  We also went through a few more parallel line proofs so the students could get more practice together in preparation for the quiz tomorrow.  The students then got started working on their review assignment.


Assignment:  Section 3.1 to 3.3 review sheet


Answers to review sheet

Properties of Parallel Lines

1.  If 2 parallel planes are cut by a 3rd plane, then intersecting lines are parallel.
2.  If a line is perpendicular to one of two parallel lines, then it is perpendicular to the other line.
3.  alt. interior angles
4.  corresponding angles
5.  same side interior angles
6.  none
7.  angles 1, 13, 15
8.  angles 2, 4, 6
9.  angles 1, 3, 5, 7, 11, 13, 15
10.  angles 2, 4, 6, 8, 10, 12, 14, 16
11.  angle 11 = 55;  angle 15 = 55
12.  angle 4 = y;  angle 3 = 180 - y
13.  x = 70;  y = 90
14.  x = 15;  y = 40

Proving Lines Parallel

1.  GA || EC
2.  GE || AD
3.  GB || ED
4.  none
5.  GB || ED
6.  GB || ED
7.  AD || GE
8.  GB || ED
9.  GE || AD
10.  x = 9;  y = 22
11.  x = 21, y = 17
12.    Statements                                                         Reasons
          3.  angle 1 congruent to angle 2                    1.  Given
                                                                                 2.  def. of angle bisector
                                                                                 3.  given
                                                                                 4.  transitive property
                                                                                 5.  if AIA congruent, then lines ||