How would you represent the weight of 750 newtons graphically?

Answer 1

Weight is a force, which is a vector quantity. I'd draw it as an arrow pointing down towards the center of the Earth. If it's a solid-body problem, then you could a draw a square or rectangle, as kris has said. If it's a particle problem, though, just use a point to represent the object.

Answer 2

I'd draw a square and write "750 N" inside the square.