1、 2018 10 20 1 ( ) A x 2 +y-2=0 B x- =1 C x 2 =1 D x 3 -2x=x 2 c = a=4cm b=9cm c= A 6cm B 7cm C 8cm D 10cm 3 ( ) A B C D 4 ( ) A 1 B C D 5 x 2 8x 1=0 A x+4 2 =17 B x 4 2 =17 C x+4 2 =15 D x 4 2 =15 6 AD=6 DB=3 AE=4 EC A 1 B 2 C 3 D 4 7 40 45% 15% . A 16 B 18 C 20 D 22 8 1 2 3 4 ( ) ( ) A B C D 9 9 (
2、) A 9 B 3 C 81 D 18 10 A B C D 10 20 11 x 3 2 =x 3 _ 12 _ 13 _ 0.1 14 60 48.6 _ 15 1000 0.6 _ 16 1.6 D DE=1.5 BD=4.5 AB=_ 17 B C AB=6 AC=10 CD= _ 18 A B A B A B _ 19 AB A 6 6 B 8 2 O AB CD C _ 20 20 40 1 2 1200 _ 4 16 21 x 2 +4x 1=0 22 2x 2 +5x=3 23 x 2 -4x=5 24 : 1 4 25 A 1 3 B 4 2 C 2 1 (1) x 1B1C
3、1 A1 B1 C1 (2) O 2B2C2 6 30 26 27 20 n 100 150 200 500 800 1000 m 58 96 116 295 601 m/n 0.58 0.64 0.59 0.605 0.601 1 2 n 0.01 3 28 x= 1 x x 2 +2ax+a 2 =0 a 29 B 8.4 E BE D A DE=3.2 CD=1.6 AB 30 D E AB AC AE=5 AB=9 CB=6 ED 31 (1) _ _ (2) 900 (3) 2 10 32 2014 2500 2016 3025 2014 2016 33 BC=120mm AD=80
4、mm PQMN PQMN QM BC P N AB AC PQMN S 4 20 34 , 32m 16m AB xm. (1) x BC (2) 120 , (3) 160 , 35 , . , AB , BC 16 , CD 8 , EF FG 2 , . 36 x x 2 2 m+1 x+m 2 +5=0 (1) m (2) x1 x2 x1 2 +x2 2 =|x1|+|x2|+2x1x2 m 37 AB BC (AB BC) 2 7 12 0 P A 1 t( ) (1) AB BC (2) P BC AP t (3) P P t 1 C 2 C . C. . 2 A c = a=4
5、cm b=9cm = c=6cm A c = a=4cm b=9cm c 3 D D = 4 D 4 1 D : ( ; ; ; ) . 5 B - 2 8x 1=0 2 8x=1 2 8x+16=1+16 x 4 2 =17 B 6 B = = EC=2 B = 7 A 45% 15% 1-45%-15%=40% A 45% 15% 8 D 4 3 6 D : 12 6 , 9 B 9 3 9 3 3 B. 10 C - C 11 x1=3 x2=4 - x 3 2 =x 3 x 3 2 x 3 =0 x 3 x 3 1 =0 1=3 x2=4 x 3 12 4 9 2 3 4 9 4 9
6、13 0.5 1550 796 0.5 14 x 3 4 1 15 600 0.6 60% 600 0.6 60% 0.6 60% 16 6.4 h = = h=6.4 17 AB=6 AC=10 BC=8 AB BC=AC CD CD= CD 18 12 8 19 3 3 AB A 6 6 B 8 2 O AB CD C A C 3 3 3 3 C 20 10 20 1200 x 40 x 20+2x =1200 x1=10 x2=20 1200 10 20 10 20 21 2 +4x 1=0 2 +4x=1 2 +4x+4=1+4 x+2 2 =5 1= 2+ x2= 2 - x 2 +4x=1 4 1 2 1 3 1 2 22 2x 2 +5x-3=0 a=2 , b=5 , c=- 2 -4ac=490 . x1= , x2=-3. - . 23 x 2 -4x=5 x 2 -4x-5=0 x-5 x+1 =0 -5=0 x+1=0 x1=5 x2=-1 - 24 = = x -1 =2 = - 25 1 A1 1 3 B1 4 2 C1 2 1 2 A 1 3 B 4 2 C 2 1 O 2B2C2 A2 2 6 B2 8 4 C2 4 2
