if you put the points into the equation y2 - y1/x2 - x1 you'll end up with a zero in the denominator, which indicates a vertical slope. Basically the slope(m) is undefined
It's really easy to tell if your answer is going to be undefined if both the x values are the same (in this case they're both 9)
The answer would be 272 because youre trying to find the decrease which is
340x.20 because you always move the percent over two decimals. you would get 68 after multiplying it then u would subtract that number by 340.
A is the answer because it costs $295 for the ticket and $271.9 in total if he drives in car. So therefore driving is less expensive.