de thi hoc ky 2 lop 9 nam 2017 2018 mon toan cua phong giao duc va dao tao vinh yen 4881

\ Prr oNG-c D &Dr-l{INu YtN oE BE CHINH THUC xrru rRA HQC rci' u NAU Hqc nt0N: roAN g 2017 - 2a18 Thdi gian ldnt bhi 90 phtit, khhng kA thdi gian giao di' I TRAC NGHIpM (2,0 tli6m) drtng Ghi vdo bdi tdm chi mQt cttib ctii A, B, C hofic D tlwdc yhuong tin trd ldi cAu Phuong trinh nio sau t16y li phucrng trinh bac ntr6t rrai ry *,y? D.2x+5y=10 C.2+5=10 A.2x+5y2=1g B.Zxy+Sy=lg A Ciu Z.Cho parabo-l (f) ,y =+vi dudng thang(d) :! =Zx-3cit tai hai di6m Khi d6, diQn tfch tam giitc OAB b{ng: c s (dvd| ' cAu Cho rtudmg trdn (o;n) c6 AB =JZn DO dai cung nh6 AB bing: A.6 (dvdt) 8.7 (dvdt) c6u Cho mQt hinh cAu c6 thc tich bang 5002gnlza 8.50r [" D tA}r cm2 C.25tt cltt2 (1,5 tri6m) cho hQ phuong trinh: (mx-v=l - (*,v ln 6n; lrr li IT^;;, : z a) Gi6i hQ Phuong trinh vdi m = -3; b) Tim m d0 hQ cl nghiQm nhat Ciu ,rr' Di€n tich mflt ciu d6 1i: cm2 - Tu LU4.N'(8,0 cli6m) u PrrAN ciu 50:o (dvdt) nR D.4 c"ry B.ZrR A nR D.9 vi B' tham sd) y deu nh4n gi6 tri UY*n trinh: x' -Zna+4m-4= (1), (x li dn; mli tham sO) (r;y) cho x vit (1,5 tliam)Cho phuong a) Tim m d6 phuong trinh (1) c6 hai nghiQm ph6n biQt; b) Tim m d6 hai nghiQm x,;x, cria phucrng trinh (1) th6a rndn: ( n-2)(*'-2)=x" +x" -8' km, sau CAu (1,5 rli6m) MOt ca nd xudi ddng tr6n mOt t