Let s = northbound train
Then
2s = southbound train
:
Distance = time * speed
4s + 4(2s) = 600
:
4s + 8s = 600
:
12s = 600
:
s = 600/12
:
s = 50 mph is the northbound train
Then
2(50) = 100 mph is the southbound train
:
:
Check:
4(50) + 4(100) = 600
Answer:
y = 
Step-by-step explanation:
Let the equation of the exponential function is,
y = a(b)ˣ
Since the graph of this function passes through two points
and (3, -1)
For the point
,
---------(1)
For second point (3, -1),
-1 = a(b)³ ---------(2)
Divide equation (2) by equation (1),
=


From equation (2)
-1 = 
-1 =
a = 8
Therefore, equation of the exponential function will be,
y = 
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