Page 2: Advanced Segment Proofs

This page presents more complex segment proofs, building on the concepts introduced in the previous page.

The fourth proof demonstrates how to prove that KL ≅ LM given that K is the midpoint of JL, M is the midpoint of LN, and JK ≅ MN. This proof combines the definition of midpoint with the transitive and symmetric properties of congruence.

Vocabulary: The symmetric property of congruence states that if A ≅ B, then B ≅ A.

The fifth proof shows how to prove that XZ = TV given that XY ≅ UV and YZ ≅ TU. This proof utilizes the segment addition property and substitution property to establish the equality of the segments.

The sixth proof demonstrates how to prove that XZ ≅ VW given that WY ≅ YZ and XY ≅ VY. This proof combines the segment addition postulate with the transitive property to establish the congruence of the segments.

Example: In the proof XY + YZ = XZ, VY + YW = VW, the segment addition postulate is applied to show that the sum of two adjacent segments is equal to the whole segment.

Page 4: Advanced Applications of Segment Proofs

This page presents more complex applications of segment proofs, incorporating various geometric properties and postulates.

The tenth proof demonstrates how to prove that Q is the midpoint of PR given that 2PQ = PR. This proof uses the segment addition postulate and the subtraction property to establish that PQ = QR, which defines Q as the midpoint of PR.

The eleventh proof shows how to prove that AD = CE given that AB ≅ CD and BD ≅ DE. This proof combines the segment addition postulate with the transitive property to establish the equality of AD and CE.

Example: In the proof AB + BD = AD, CD + DE = CE, the segment addition postulate is applied twice to show that the sum of two adjacent segments is equal to the whole segment on both sides of the equation.

The twelfth proof demonstrates how to prove that HI ≅ JK given that GI ≅ JL and GH ≅ KL. This proof employs the segment addition property, substitution property, and subtraction property of equality to establish the congruence of HI and JK.

Vocabulary: The subtraction property of equality states that if you subtract the same quantity from both sides of an equation, the equation remains true.

These advanced proofs reinforce the importance of logical reasoning and the application of multiple geometric properties in solving complex segment problems.

Page 1: Introduction to Segment Proofs

This page introduces the concept of segment proofs in geometry and provides several examples to illustrate the process.

The first proof demonstrates how to prove that 2DE = DF given that E is the midpoint of DF. The proof uses the definition of midpoint, the addition property of equality, and the segment addition postulate to establish the relationship.

Definition: A midpoint is a point that divides a line segment into two equal parts.

The second proof shows how to prove that L is the midpoint of KM given that KL ≅ LN and LM ≅ LN. This proof utilizes the transitive property of congruence to establish that KL ≅ LM, which leads to the conclusion that L is the midpoint of KM.

Example: In the proof KL ≅ LN, LM ≅ LN → KL ≅ LM, the transitive property of congruence is applied to show that two segments are congruent to a common segment, therefore they are congruent to each other.

The third proof demonstrates how to prove that PS ≅ TU given that PQ ≅ TQ and UQ ≅ QS. This proof employs the segment addition postulate and the definition of congruence to establish the relationship between the segments.

Highlight: The segment addition postulate states that the length of a whole segment is equal to the sum of the lengths of its parts.