Select the correct answer from each drop-down menu.
Given:
and
are complementary angles

intersects
at point O

Prove:

Diagram shows line segment AD contains point O. Segment OB is drawn and segment OC is drawn between segments OB and OD. Angles COD and BOD are acute angles.

Statements Reasons
1.
and
are complementary angles;

intersects
at point O

1. given
2.
2. definition of complementary angles
3.
3. substitution property of equality
4.
and
are supplementary angles 4. linear pair theorem
5.
5. definition of supplementary angles
6.
6. substitution property of equality
7.
7. subtraction property of equality
8.
8. substitution property of equality
9.
9. definition of congruent angles
There is a step missing in the proof. Identify where in the proof there is a missing step and what this step should be.
There is a missing step between
because the student did not state

. This statement is true because of the
.