Among these three points A1,2,B2,3,C−1,4 the pair of points which are on the same side of the line  2x−y+4=0 are x1,y1.x2,y2 then the value of x1+x2+x3+x4 is

If LA and  LB are of same sign then the points A,B  lies on the same side of the line  L=0Here, LA=21−2+4=4>0,LB=22−3+4=9>0 and  LC=2−1−4+4=−2<0Hence, A1,2,B3,4 lies on the same side of the line  2x−y+4=0Therefore, 1+2+3+4=10.