1、 2017-2018 120 120 1. . 2. 2B . 3. . 6 3 18 1. 2018 1 = 2. 3 . x = 3 9 2 x x . 4. 4cm 9cm _ 5. 9 2 kx x k = 6. 9 _ 8 4 32 7 A B C D 8. A 1cm 2cm 4cm B 4cm 6cm 8cm C 5cm 6cm 12cm D 2cm 3cm 5cm 9. BC=BE B AB=DB D DB=AB E AC=DE C C D 9 10. A 4 2 3 x x x B 2 2 ) )( ( y x y x y x C 2 2 ) 2 ( x x x x D 4
2、2 2 3 3 3 x xy y x 11. A 3x+2x-1=5x-1 B (3a+2b)(3a-2b)=9a 2 4b 2C.x 2 +x=x 2 (1+ ) D 2x 2 -8y 2 =2(x+2y)(x-2y) 12. ABC AD=8 CD 12 13 14 13. A B D C E A B C D 14 ABC A AB MN AC D DBC AB m BC n DBC ( ) A m n B 2m n C m 2n D 2m n 9 70 15. 6 2 2 24 ab a b a b 16. 6 x5 4 2x 3 3 2x . 17. 6 ( 1 1 1 1 x x )
3、 2 2 2 x x , -1 1 4 x A= E 19. 6 ABC=38 ACB=100 AD BAC AE BC DAE . 18 ( 19 ) 20. 10 ABC 90 ,D AB AD BC A AF AB , AF BD , DC DF CF CDF . 21. 22. ABC A 1 1 B 4 2 C 3 4 ABC y A1B1C1 A1 B1 C1 x P PA+PB P y Q S AOQ= 1 2 S ABC Q B A F D C 23 12 ABC 1 D AB E AC BD CE BE CD F BF CF 2 D AB E AC BD CE BE CD F
4、 BFD FBD 23 2017 2018 6 3 18 1 1 2 3 3 4 22cm 5 6 6 135 8 4 32 7 8 9 10 11 12 13 14 C B A C D B D A 9 70 15. 6 = 2 2 3 4 4 4 ab ab b = 3 4b16. 6 1 7 7 12 8 5 ) 3 2 ( 4 5 4 3 2 5 3 2 x x x x x x x x x :x=1 x=1 17. 6 1 1 1 x 4 4 x x 4 x 1 - x 2 1 - x 1 x - 1 x 2 2 AB DE B= ABC 19. 6 ABC=38 ACB=100 BAC
5、=180 38 100 =42 180 . AD BAC BAD=21 ADE= ABC+ BAD=59 . AE BC E=90 DAE=90 59 =31 . 20. 10 CDF AF AD ABC=90 FAD= DBC FAD DBC B A F D C FAD DBC SAS FD=DC CDF FAD DBC FDA= DCB BDC+ DCB=90 BDC+ FDA=90 CDF 21. 30 3000 7000 5 . 1 3000 x x 200 x 200 x 20 200 3000 7000 22. 1B1C1 A1 -1 1 B1 -4 2 C1 -3 4 1 A A 3 4 BA x P P 2 0 Q S AOQ= 1 2 S ABC 2 AD y D Q 0 y OQ y AD 1 S ABC 1 1 1 3 3 3 1 2 1 3 2 2 2 2 7 2 S AOQ= 1 2 S ABC 1 1 7 | | 1 2 2 2 y 7 2 y 7 2 y Q 0 7 2 0 7 2 1 2 23 12 ABC= BCD BCD= BCD= CBE BCD= FBD= FDB FBD= FDB FBD FBD FBD= 22 23 A1 C1 B1 BDF= DBF BDF +2x+2x=18
