Answer:
GF = 25.2
Step-by-step explanation:
GF/BC = (AD-FE)/AD
GF = BC(AD-FE)/AD = 36(20-6)/20
GF = 25.2
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The ratio of GF to BC is the ratio of DE to DC. The ratio of FE to AD is the ratio of CE to CD. That is ...
GF/BC = (CD-CE)/CD = 1 - FE/AD = (AD -FE)/AD . . . . . as above