青岛版八年级上册数学书第7页习题1.1答案
1第7页习题1.1第1题答案
解:AB与DC,AF与DE,BF与CE分别是对应边;
∠A与∠D,∠B与∠C,∠AFB与∠DEC分别是对应角。
2第7页习题1.1第2题答案
解:AB = AC,AE = AD,BE = CD,
∠B = ∠C,∠BEA = ∠D,∠EAB = ∠DAC
3第7页习题1.1第3题答案
(1)11 5
(2)85°,30°,65°,65°
4第7页习题1.1第4题答案
解:AD = BE = CF,AF = BD = CE,DF = ED = FE,
∠A = ∠B = ∠C,∠ADF = ∠BED = ∠CFE,
∠AFD = ∠BDE = ∠CEF,∠EDF = ∠DEF = ∠DFE,
∠ADE = ∠BEF = ∠CFD,∠BDF = ∠CED = ∠AFE.
5第7页习题1.1第5题答案
解:(1)因为△ABE ≌ △ACD,
所以BE = CD = 6,所以BE - DE = CD - DE = 6 - 2,
即BD = EC = 4,
所以BC = BD + DE + EC = 4 + 2 + 4 = 10.
(2)因为△ABE ≌ △ACD, 所以∠BAE = ∠CAD,
所以∠BAE - ∠DAE = ∠CAD - ∠DAE,
即∠BAD = ∠CAE = 30°,
所以∠DAE = ∠BAC = ∠BAD - ∠CAE = 75° - 30° - 30° = 15°
6第7页习题1.1第6题答案
解:(答案不唯一)
(1)如图1 - 1 - 26所示。
(2)如图1 - 1 - 27所示。
(3)如图1 - 1 - 28所示。它们都全等。