I would say that the correct answer is D. because y is always the numerator while x is the denominator for the equation y2 - y1/x2 - x1 which means if there is two y's or two x's on the same line you subtract the second one from the first one. If there is only one y and/or x and the other is 0 on the same line, it stays at y or x without subtracting y2 - y1 or x2 - x1.
Since b is on the y coordinate and -a is on the x coordinate, you would make it b/a while -a is gonna be a positive since the lines are going up and to the right. Now, since c is the y coordinate and d is the x coordinate, make C the numerator and d the denominator since y is always the numerator and x is the denominator for these parallel line figures on the graph and the equation will be equaled to the fraction to the other fraction for parallel lines.
So, your answer would be D. b/a = c/d
Hope this helps, and is correct!
<em>~ ShadowXReaper069</em>
Answer:


And then the percentage between 24 and 40 would be 
Step-by-step explanation:
For this problem we have the following parameters given:

And for this case we want to find the percentage of lightbulb replacement requests numbering between 24 and 40.
From the empirical rule we know that we have 68% of the values within one deviation from the mean, 95% of the values within 2 deviations and 99.7% within 3 deviations.
We can find the number of deviations from themean for the limits with the z score formula we got:

And replacing we got:


And then the percentage between 24 and 40 would be 
The similarity ratio is 338 : 73.
You cannot simplify this ratio any further, since 73 is a prime number.