如图已知抛物线y=ax平方加bx+5经过a负0b负四负三两点与x轴的另一个交 ...答:(1)∵抛物线过O(0,0),A(1,-3),B(-1,5)三点,解得 a= 1 b=-4 c=0 ;∴抛物线的解析式为y=x2-4x;(2)抛物线y=x2-4x与x轴的另一个交点坐标为C(4,0),连接EM;∴⊙M的半径为2,即OM=DM=2;∵ED、EO都是⊙M的切线,∴EO=ED,△EOM≌△EDM;∴S四边形EOMD=2S△...
如图,在直角坐标系中,抛物线y=ax^2+bx+c(a不等于0)与x轴交于点A(-1...答:抛物线y=ax^2+bx+c(a不等于0)与x轴交于点A(-1,0),B(3,0)两点, 则该抛物线可表示为 y = a(x + 1)(x -3) = ax² -2ax -3a 抛物线交y轴与点C(0,3), 3 = -3a, a = -1 y = -x² + 2x + 3 E为线段OC上的三等分点, E(0, 1)或E(0, 2)设P(p...
如图已知抛物线y=ax平方+bx+c(a答:1.y=-x^2+2x+1可知:C(0,1);y=-x^2+2x+1=-(x-1)^2+2,可知D(1,0);F(1,2),由C与E关于对称轴(x=1)对称,可知E(2,1)所以,此四边形CDEF为正方形.2.①因抛物线方程为y=ax^2+bx+c,则C(0,c);D(-b/2a,0);如CDEF为正方形,则D与F必关于直线CE对称.则F(-b/2a,2c)...
如图,抛物线yax平方+bx-2(a不等于0)过点A(-1,0),B(4,0),与y轴交与点...答:y=ax^2+bx-2 A(-1,0),B(4,0)a=0.5,b=-1.5 C(0,-2)(1)y=0.5x^2-1.5x-2 D(1.5,-3.125)(2)E(m-1,0)k(EF)=k(BD)=1.25,k(AD)=-1.25 AD:y=-1.25(x+1)...(1)EF:y=1.25(x+1-m)...(2)yF=-0.625m s=(1/2)*m*(3.125-0.625m)=0.3125...