You meant "15 mph, faster" not "15 mpg faster", right?
distance = speed * time
distance = 425 miles
time = 5 hours
Sal's speed = s
Tony's speed = s + 15
Since they drove in opposite directions, the speed between them is the sum of the speeds.
distance = speed * time
425 = (s + s + 15) * 5
85 = 2s + 15
70 = 2s
s = 35
s is Sal's speed and is 35 mph.
Tony's speed is 15 mph faster, so Tony's speed = 35 mph + 15 mph = 50 mph
Answer:
Sal's speed was 35 mph
Tony's speed was 50 mph
