You have to move variables on one side and constants on the other
aby - b + b = c + b
aby = c + b
y = (c + b)/ab
It's a linear function: y = mx + b
We have (138; 112.96); (209; 142.78)
substitute the values of x and y to the formula of slope m:

Now we have: 
We must find b. Substitute the value of x and y from first pair of numbers:

Answer: y = 0.42x + 55
The unit rate for the problem is 16
<h3>Answer:</h3>
The cube of twice a number is
.