Answer: 32.50 [No $ sign as per the directions]
Step-by-step explanation:
The graph appears as a straight line. That means we can pick any two points and calculate the slope, m, for the equation of a straight line: y = mx + b
We can pick any two points, so I'll pick two that do not require interpretation of the graph. Points (0,0) and (8,20) look good since we can feel relatively confident that the line crosses those two points since they fall on the graph marking lines.
Slope is Rise/Run, or the change in y per the change in x. For these two points, we have:
Rise = (20 - 0) or 20
Run = (8 - 0) or 8
The slope is Rise/Run. 20/8, or 2.5
[The units for the slope are $/lb, but units are to be left out of the answer]
The equation is now y = 2.5x + b
b is the y-intercept, the value of y when x = 0. We can see that y = o when x = 0, so b is zero.
The final equation is y = 2.5x
Use x = 13 lbs to find the cost of 13 lbs of blueberries.
It is 13*2.5 = 32.50
