... 30 40 -10 -20 A -20 B -30 -30 y y 40 40 30 30 20 20 10 10 x -30 -20 -10 10 20 30 x 40 -30 -10 -30 -10 10 -10 -20 C -20 -20 D -30 20 30 40 Câu 173 Hm s y = 3x2-4x+1 : Câu 174 : 3 3 3 3 3 2 A ng ... y=ax2+bx +2 cú nh I(1;3) Khi ú (P) cú phng trỡnh: : Câu 1 02 : A y = x -4x +2 2 B y= -x +2x +2 A (P): y= -x2+2x +2 C (P): y= x2-2x +2 Hm s y= x +1 cú xỏc nh l: x A D = R 2 B D = R\{-1} C y=2x +x +2 C ... Câu 23 5 : D A B (2; 2) , (3; 1), (-3; 6) D ( -2; -2) , (1; -2) , (-6; 3) x + y + xy = Nghim ca h phng trỡnh x y + y x = 2 l A (1; 2) , (2; 1) 2 B ( ; 2) , (2; ) 1 C (2; ), ( ; 2) D (2 + 3; 3), (2...