The slope is the same as the gradient
y=mx+c where m is the gradient and c is the y intercept
y=-5x-9
Therefore the 'slope' is -5 i.e. it goes down 5 every 1 across.
201.25 because (175x15)+175=201.25 (i dont know if im right)
So that would be the total bill divided by 4
17.84/4=16/4+1/4+0.84/4=4+0.25+0.21=4.46
each person's share was $4.46
It is a representation of a number