1.已知直线l1:kx−y+3k+5=0l_{1}:kx-y+3k+5=0l1:kx−y+3k+5=0恒过点AAA,已知B(2,8)B(2,8)B(2,8),动点PPP在直线l2:x−y+1=0l_{2}:x-y+1=0l2:x−y+1=0上,则∣PA∣+∣PB∣\vert PA\vert +\vert PB\vert∣PA∣+∣PB∣的最小值为((( )))