Practice A Theorems

                                                                    Theorem 3.1:
All right angles congruent.

                                                                    Theorem 3.2:
 If two lines are perpendicular, then they intersect too form four right angles.

                                                                      Theorem 3.3:
If two lines intersect to form adjacent angles, then the lines are perpendicular.

                                                                      Theorem 3.4:
If two sides of adjacent acute angles are perpendicular, then the angles are complementary.