Answers:
Across:
- Bisects
- Given
- ABD
- Angle Bisector
- Reflexive
- ABD
- AAS
Down:
- Given
- CM = MK
- Midpoint
- NKM
- Alternate Interior
- CME
- Vertical
- ASA
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Explanations:
Always start with the given statements and build toward the thing you want to prove. The first line(s) will basically be restating the given facts word for word.
The term "bisect" means to "divide in two equal pieces". Angle ABC is split into the two equal pieces of angles ABD and CBD, hence ABD = CBD. Segment CK is split into the equal pieces of CM and MK, meaning that CM = MK.
The reflexive theorem says any segment is congruent to itself, so BD = BD.
Vertical angles are formed when we intersect two lines to form an X shape. The vertical angles are opposite one another and always congruent.
Alternate interior angles are always congruent when we have parallel lines.
The AAS (angle angle side) congruence theorem says that two triangles are congruent if we have two pairs of congruent angles, and a pair of congruent sides. The congruent sides are not between the angles mentioned. The order matters.
AAS is slightly different from ASA. With ASA, the congruent sides are between the congruent angles.