Answer:
12 mph and 16 mph
Step-by-step explanation:
distance = speed * time
56 = s * 2 + (s - 4) * 2
56 = 2s + 2s - 8
56 = 4s - 8
64 = 4s
16 = s
s = 16
s - 4 = 12
11 i think