求直线y x-1被抛物线y方 4x截得的线段的中点坐标怎么想,抛物线与直线相交求直线斜率

y1^2=4x1y2^2=4x2(y1+y2)(y1-Y2)=44(x1-x2)(y1-y2)/(x1-x2)=4/(Y1+y2)K=1=4/(Y1+y2),YI+Y2=4.(YI+Y2)/2=2,y=x-1,2=X-1,X=3(3,2)