Question

PLEASE HELP THERE ARE TWO PARTS!!

Answer 1

Answer:

The constant of proportionality of the graph is 0.75

Step-by-step explanation:

The coordinates of the points on the lines are;

(400, 300), (250, 187.5), and (120, 90)

Which can be written in a tabular form as follows;

Number of US dollars   ${}$                       Number of euros

120                                 ${}$                        90

250                                ${}$                        187.5

400                                ${}$                        300

Given that the graph is a straight line graph, we can represent the graph with the straight line equation, y = m·x + c

Where;

c = The y-intercept (where the graph meets the y-axis) = 0

m = The slope = The constant of proportionality

$Slope, \, m =\dfrac{y_{2}-y_{1}}{x_{2}-x_{1}}$

$m =\dfrac{300-90}{400-120} = \dfrac{210}{280} = 0.75$

We have, y = m·x = 0.75·x.

Therefore, the constant of proportionality of the graph = 0.75.