Final answer:
The equation y = 17.5x represents the total number of miles a train travels in 2 hours. By substituting the value of x with 2, the total number of miles can be calculated to be 35 miles.
Step-by-step explanation:
The equation y = 17.5x represents the total number of miles a train travels in 2 hours, where y is the dependent variable and x is the independent variable. In this equation, the coefficient 17.5 represents the rate of travel, which is 17.5 miles per hour.
To find the total number of miles the train travels in 2 hours, we need to substitute the value of x with 2 in the equation. Therefore, y = 17.5 * 2 = 35 miles.
Hence, the correct answer is option A: 35 miles.