Answer:
![y=15x](https://tex.z-dn.net/?f=y%3D15x)
![y=-x](https://tex.z-dn.net/?f=y%3D-x)
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
or ![y=kx](https://tex.z-dn.net/?f=y%3Dkx)
In a proportional relationship the constant of proportionality k is equal to the slope m of the line and the line passes through the origin
case A) ![y=15x](https://tex.z-dn.net/?f=y%3D15x)
Is a linear equation that passes through the origin
therefore
The case A) represent a proportional relationship
case B) ![y=-x](https://tex.z-dn.net/?f=y%3D-x)
Is a linear equation that passes through the origin
therefore
The case B) represent a proportional relationship
case C) ![y=-5(x+1)](https://tex.z-dn.net/?f=y%3D-5%28x%2B1%29)
Is a linear equation but not passes through the origin
therefore
The case C) does not represent a proportional relationship
case D) ![y=5x+1](https://tex.z-dn.net/?f=y%3D5x%2B1)
Is a linear equation but not passes through the origin
therefore
The case D) does not represent a proportional relationship