Statements Reasons
Drag these
FB IEC
m ABF m&FBC = 180; m&ECD+ m ECB -
180
Given
Linear pairs are supplementary
Definition of Supplementary
Subtraction Property of Equality
40+ m2FBC = 180 ; 140+ m2ECB = 180
Same-side Interior Angles are Supplementary
Converse
Substitution Property
m FBC is supplementary to m ECB
M ABF = 40;mECD = 140
m FBC + m2ECB = 180
Addition Property of Equality
m_FBC = 140;m ECB = 40