here's the answer to your question
Answer:
2.8 hours
Step-by-step explanation:
Distance = rate * time
If the west-bound train travels at a rate of 80 mph for t hours, then the distance it travels is 80t.
If the east-bound train travels at a rate of 90 mph for t hours, then the distance it travels is 90t.
The distance between the trains after t hours is 476; therefore, the distance of the west-bound train plus the distance of the east-bound train equals the total distance between them, 476:
80t + 90t = 476 and
170t = 476 so
t = 2.8 hours
F(5)= 5^2+4(5) = 25+20=45
g(6)= 2(6)+2 = 14
f(5)+g(6) = 45+14 = 59