Answer:
y=4x
Step-by-step explanation:
In a proportional relationship, two values always have the same ratio to each other. This means that when we look at the equation of a line, y=mx+b, where m=slope and b=how much more plus the slope y is, there cannot be a "b" value.
An example of this is:
If the slope is 3,
y=3x
If x=2, y=6
If x=5, y=15
We can see that for every pair of coordinates, the ratio (5) between x and y remain the same.
y cannot have anything added to i (ex: y=3x+1), otherwise the ratio would change.
Ex:
If the equation is y=3x+1,
If x=1, y=4
If x=2, y=7
We can see that the ratios between the two numbers (1/4, 2/7) are not the same.
In this problem, the only equation without "b" is y=4x. Therefore, the answer is y=4x.