Answer:
3a. yes
3b. y= 75x
3c. 600 mi
3d. 10 inches
Explanation:
3a: if you divide the y by the x, you'd get 75 everytime, meaning it's proportional.
3b: y would equal the amount of inches multiplied by 75, so y=75x
3c: you can use the equation and substitute the x for 8, so y=75(8), giving you 600 miles
3d: you can also use the equation in reverse, if the actual miles is 750, then this is your y, so it would look like 750=75x and to solve you'd divide, 750/75, giving you 10 inches