相交线与平行线几何语言训练练习(1)班级 姓名1.完成推理填空:如图:直线AB、CD被EF所截,若已知AB//CD,求证:Zl = Z2 o证明:AB//CD (已知),Z1 = Z ( 两直线平行, )又VZ2 = Z3, ( ))oAZ1 = Z2 (2.如图:已知ZB=ZBGD, ZDGF=ZF,求证:ZB +ZF =180° o证明:V ZB=ZBGD (已知)AE.•.AB〃CD ()VZDGF=ZF;(已知)C\g d.•.CD〃EF ()E \F\ F「・AB〃EF ( )AZB + ZF =180° ( )3.已知,如图,ZBAE+ZAED=180° , ZM=ZN,试说明:Z1=Z2.解:V ZBAE+ZAED=180° (已知)...〃 ( )・•・ ZBAE= ZAEC ( )XV ZM=ZN (已知)...〃 ( )ZNAE= ZAEM ( )ZBAE-ZNAE=/.即 Z1=Z24.如图,EF〃AD, Zl=Z2, ZBAC =70° o将求ZAGD的过程填写完整解:VEF/7AD ()AZ2VZ1 = Z2 ()Zl=Z3o (AB〃... ZBAC +=180° o (ZBAC = 70° ,(E・.・ZAGD =5.如图 11,Z5=ZCDA =ZABC,Z1=Z4,Z2=Z3,ZBAD+ZCDA=180°,填空:VZ5=ZCDA (已知)VZ5=ZCDA (已知),又VZ5与匕BCD互补ZCDA 与互补(邻补角定义).\ZBCD=Z6 (6.如图, 已知:DELAO 于 E, BO±AO,ZCFB=ZEDO 证明:CF〃DO.\ZDOF=ZCFB ( )...CF〃DO ( )7.看图填空:⑴如图,因为ABLAD, CDLAD,(已知)所以 ==90 °( )又因为匕1 = Z2 (已知)所以ZBAD-Z1 =ZCDA-Z1,即匕ADF = ZDAEFO所以—〃—( )8.如图,因为BE平分ZABC (已知)所以 =2/1(因为CE平分ZBCD (已知)所以 = 2/2 (所以 + = 2Z1+2Z2 = 2 (Z1 + Z2)所以=2X90° =180°,又因为匕1 +匕2 = 90° (已知)9.如图 AB〃CD/1=/2,/3=/4,试说明 AD〃BE所以—〃求证:AD平分/BAC.证明:•「ADLBC,().../ADG=90°()VEGXBC,( ).../EGC=90°,().../ADC=/EGC=90°,.EG〃AD,().../1=/E,()/2=/3,()•「/E=/3,( ).../1=/2,()解:.「AB〃CD (已知).・./4=/ ( ).「/3=/4 (已知).../3=/ ( )•「/1=/2 (已知)・../ 1+/CAF=/2+/CAF ( )即 / =/ ( ).../3=/...AD〃BE( )10.视图填空:图,已知:ADXBC于D, EGXBC于G,/E=/3,即AD平分/BACDC11.如图,E点为DF上的点,B为AC上的点,匕1 = Z2,ZC=ZD,那么DF〃AC,VZ1 = Z2 ( )Z2=Z3,Z1 = Z4 ( )AZ3=Z4 ( )...〃 (AZC=ZABD (VZC=ZD (?.ZD=ZABD (...DF〃AC( )12.如图,已知Z1 = ZB,求证:Z2=ZC。