已知一次函数y=3/2x+m和y=nx+p的图象都经过点A(-2,0)且与y轴分别交于B、C两点,S△ABC=4,求m、n、p的值
问题描述:
已知一次函数y=3/2x+m和y=nx+p的图象都经过点A(-2,0)且与y轴分别交于B、C两点,S△ABC=4,求m、n、p的值
答
A(-2,0)代入y=3/2x+mm=3y=3/2x+3B(0,3)C(0,p)S△ABC=AO*BC/2=2*|p-3|/2=4p-3=±4p=7 p=-1A(-2,0)代入y=nx+70=-2n+7n=7/2A(-2,0)代入y=nx-10=-2n-1n=-1/2 m=3 p=7 n=7/2m=3 p=-1 n=-1/2