As shown in the figure, the known points E and C are on the line BF, be = CF, ab ‖ De, ∠ ACB = ∠ F
It is proved that: ∵ ab ‖ De, ∵ B = ∵ def. ∵ be = CF, ∵ BC = EF. ∵ ACB = ∵ F, ∵ B = ≌ defbc = EF ≌ ACB = ≌ F, ≌ ABC ≌ def (ASA)
It is known that △ ABC is equal to △ def, a = 52 °, B = 32 ° 12 ', de = 10cm. Calculate the degree of ∠ DFE and the length of ab
AB=10,∠DFE=95°48′
RELATED INFORMATIONS
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