Loading...
Writing Proofs
A
B
C
D
E
F
. . . .

Properties of Equality and Congruence

The algebraic properties of inequality can be applied in the following inequalities for segments and angles:

Inequalities for Segments
  • Line segment AB is greater than line segment CD, denoted by AB ¯ > CD ¯ , if any only if AB>CD.
  • Line segment AB is less than line segment CD, denoted by AB ¯ < CD ¯ , if and only if AB<CD.

Inequalities for Angles
  • Angle A is greater than angle B, denoted by ∠A>∠B, if and only if m∠A>m∠B.
  • Angle A is less than angle B, denoted by ∠A<∠B, if and only if m∠A<m∠B.

Whole-Part Inequality
  • If AC=AB+BC and BC>0, then AC>AB.
  • If m∠ABC=m∠ABD+∠BDC, then m∠ABC>m∠ABD.