Given: ∠DFE = ∠CDF, CF ǁ DE, FG=2x, DG=18

Prove: x=9

2x=18
∠DFE = ∠CDF, CF ǁ DE, FG=2x, DG=18
Given
Equal alternate interior angles mean parallel lines
x=9
CDEF is a parallelogram
FG = DG
CD ǁ FE
The diagonals of a parallelogram bisect each other
CE bisects DF at G
Substitution
Definition
Definition
Algebra