The graph shows the relationship between the United States dollar and the euro, the currency of the European Union, in December 2011. Part A: What is the constant of proportionality shown in the graph?

The constant of proportionality is 3/4

Step-by-step explanation:

Here, we want to write the constant of proportionality in the given graph .

To find the constant of proportionality, we need to find the slope of the line.

We can get the slope by using two of the points on the line.

Mathematically, slope of a line m is;

m = (y2-y1)/(x2-x1)

Let (x1,y1) = (120,90) and (x2,y2) = (400,300)

slope will be ( 300-90)/(400-120) = 210/280 = 3/4

a

step-by-step explanation: