Answer:
C. The value of a is the number that the x-values are multiplied by to get to the corresponding y-values. So, a = 3.
Step-by-step explanation:
Given the points (5, 15) and (-5, -15) are plotted using the equation y = a•x, this shows a proportional relationship between y and x.
Thus using any of the points, say (5, 15), x = 5, and y = 15, thus:
a = y/x = 15/5
a = 3
Therefore, the value of a, which is 3, is the number that the x-values, 5 and -5, are multiplied by to get the corresponding y-values, 15 and -15.
As we can see, if we multiply each of the x-values by 3, it will give us their corresponding y-values.