Chapter 1: Making Connections with Proof

Flashcards covering geometry definitions, rules of logic, and common reasons used in deductive reasoning and proofs.

Congruent Angles (from measure)

If two angles have the same measure, then the angles are congruent.

Midpoint

If a point is a midpoint of a segment, then it splits the segment into two congruent segments.

Angle Trisection

If three congruent angles are formed by internal rays, then the rays trisect the large angle (e.g., rays $BD$ and $BE$ trisect $\angle ABC$).

Angle Bisector Reason

If a ray bisects an angle, then it divides the angle into two congruent angles.

Right Angle Congruence

If two angles are both right angles, then they are congruent.

Right Angle Measure

If an angle is a right angle, then its measure is $90^\circ$.

Segment Bisector

If a ray bisects a segment, then it divides the segment into two congruent segments.

Invalid Diagram Assumptions

In geometric proofs, you cannot assume angles are right angles based only on a diagram without explicit labels or given statements.