straight line

here equation will be $ax_{1}+bx_{2}+cx_{3}+dx_{4}=0$

here no polynomial degree of $x$

and also there are atleast 2 distinct point

and the line passes through these points

So, this must be a straight line

here equation will be $ax_{1}+bx_{2}+cx_{3}+dx_{4}=0$

here no polynomial degree of $x$

and also there are atleast 2 distinct point

and the line passes through these points

So, this must be a straight line