Answer:
y = 4.25x
Step-by-step explanation:
The function that we want to construct is a linear function:
y=mx+b
To find the values of the parameters m and b, we just need to use the two points that the question gave:
in two weeks, he used 8 1/2 = 8.5 cups, so for x = 2 we have y = 8.5.
in five weeks, he used 21 1/4 = 21.25 cups, so for x = 5 we have y = 21.25.
Then, we apply these values in the equation:
8.5 = 2m + b
21.25 = 5m + b
Subtracting the first equation from the second, we have:
3m = 12.75
m = 4.25
Now we use the value of m in the first equation to find the value of b:
8.5 = 2*4.25 + b
8.5 = 8.5 + b
b = 0
So, our equation will be y = 4.25x
