two cars start out together from the same place. they travel in opposite directions, with one of them traveling 15 miles per hour faster than the other. after four hours, they are 596 miles apart. how fast is each car traveling?

12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901235678901234567890123456789012345678901234567890123456789012345678901234567890123467891234567890123456789012345678901235678012345678901234567890123456789012345678901234567890123456789012345345678901234567012456701467890123456789012345678901234567890123456789012345678901234569013123123456789012345678901234567890