Answer:
[tex]y=-x[/tex]
Step-by-step explanation:
we know that
A relationship between two variables, x, and y, represent a proportional variation if it can be expressed in the form [tex]y/x=k[/tex] or [tex]y=kx[/tex]
In the proportional relationship the constant of proportionality k is equal to the slope m and the line passes through the origin
case A) [tex]y=-x[/tex]
Is a linear equation that passes through the origin
therefore
Represent a proportional relationship
case B) [tex]y=-5(x+1)[/tex]
Is a linear equation but not passes through the origin
therefore
Not represent a proportional relationship
case C) [tex]y=1/(5x)[/tex]
Is a inverse variation
case D) [tex]y=5x+1[/tex]
Is a linear equation but not passes through the origin
therefore
Not represent a proportional relationship
