Answer:
The value of b would have to be 2.
Step-by-step explanation:
In order to find this value, we need to note that in order for this line to be parallel to the y-axis, the x values must be equal. So we can set the variable x value in the first ordered pair equal to the x value in the second.
5b - 1 = 9
5b = 10
b = 2
