Download Lines are - Riverside Local Schools

Lines are 
Def  lines
Lines are ll
If alt. int. <’s =, lines ll
If corr. <’s =, lines ll
If alt. ext. <’s =, lines ll
If s-s int. <’s =, lines ll.
Triangles are congruent
Triangles are similar
A quadrilateral is a parallelogram
A point is a midpoint of a segment
Def of midpoint
Sum of two angles = 180°
Angle Addition Postulate
Def of supplementary angles
If lines ll, s-s int. <’s = 180
Additional Reasons:
 Angles on a line add up to 180
 Angles around a point add up to 360

 Sum Theorem
 Ext.  Theorem
A line bisects a segment
Segments are equal or congruent
Angles are equal or congruent
Def of midpoint
Def of angle bisector
transitive or substitution property (sub w/= only)
Vertical s are 
Reflexive
All right s are 
transitive or substitution property (sub w/= only)
If lines are //, corr. s are 
If lines are //, alt. int. s are 
If lines are //, alt. ext. s are 
Base s Theorem
Reflexive
continued
Angles are supplementary
Def supplementary s
If lines are //, s-s int. s are supplementary
Linear pairs are supplementary
An angle is a right angle or an angle = 90°
Def right angle
Def  lines
Angles are complementary
Def complementary s