1.将E(-8,0)带入y=kx=50=-8k+5k=5/82.S=0.5*6*y =3y =3(5/8 x+5) =15/8 x+15 -8<x<03.将 S= 带入S= 15/8x+1527/8=15/8x+15x=-31/5∴P(-31/5,9/8)