ANSWER
y = 2x
Step-by-step explanation
We have that after 2 hours, 4 inches of snow had fallen.
We also have that the snow continues falling at this rate.
We are told to use x as the variable. This means that the hours the snow falls is represented by x.
It also means that the amount of snow is represented by y.
A linear equation is given generally as:
y = mx + c
where m = slope
c = y intercept
The slope basically means the rate of change of y values with respect to x values.
Since snow continues falling at the rate of 4 inches (y) every 2 hours (x), therefore, the rate (slope) is:
Now, we will use the point-slope method to find the equation:
where (x1, y1) is any set of points
We have a set of points already (x1, y1) as (2, 4) (remember 2 hours, 4 inches), so:
=> y - 4 = 2(x - 2)
y - 4 = 2x - 4
=> y = 2x - 4 + 4
y = 2x
Therefore, that is the equation that represents the amount of snow fallen after x hours.