The formula of t in terms of s ,
,
is

The value of t when s = 310 ,
= 75 ,
= 80 is 2 hours
Step-by-step explanation:
Two trains left the cities A and B at the same time and headed towards
each other
- The cities are s miles apart
- The first train was traveling at the speed of
mph - The second train was traveling at the speed of
mph - After t hours the two trains met each other
∵ The cities are s miles apart
∵ After t hours the two trains met each other
∴ s =
+
, where
is the
distance that the 1st train moved in t hours and
is the distance that the 2nd train moved in t hours
∵ s = v t
∴
=
t
∴
=
t
- Substitute them in the equation of s
∴ s =
t +
t
- Take t as a common factor in the right hand side
∴ s = t (
+
)
- Divide both sides by (
+
)
∴ 
The formula of t in terms of s ,
,
is

∵ s = 310 m/h
∵
= 75 m/h
∵
= 80 m/h
- Substitute these values in the formula of t above
∴ 
∴ t = 2 hours
The value of t when s = 310 ,
= 75 ,
= 80 is 2 hours
Learn more:
You can learn more about distance, speed and time in brainly.com/question/1748290
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