The distances (y), in miles, of two cars from their starting points at certain times (x), in hours, are shown by the equations below:

car a:
y = 52x + 15

car b:
y = 46x + 63

after how many hours will the two cars be at the same distance from their starting point and what will that distance be?

8 hours, 510 miles
8 hours, 431 miles
7 hours, 510 miles
7 hours, 431 miles