Answer:
Step-by-step explanation:
The generic formula for the n-th term of an arithmetic sequence is ...
an = a1 +d(n -1)
where an is the n-th term and a1 is the first term.
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Here, you have a1 = -12 and d = 4. Putting these numbers into the formula gives you what you are asking for:
an = -12 +4(n -1)
Answer:
34.22 liters
Step-by-step explanation:
Step one:
Given data
A car averages 28.5 miles per gallon of gasoline
How many liters of gasoline will be needed for a trip of 415 km
let us convert 415km to miles first
1 km is 0.621371 miles
415km is x miles
cross multiply we have
x= 415*0.621371
x=257.86 miles
Step two:
if 1 gallon of gasoline will cover 28.5 miles
the x gallons will cover 257.86 miles
cross multiply we have
28.5x= 257.86
divide both sides by 28.5
x= 257.86/28.5
x=9.04 gallons
Step three:
let us convert gallons to liters
1 gallon is 3.78541 liters
9.04 gallons will be x liters
cross multiply we have
x=9.04*3.78541
x= 34.22 liters
A minimum because the function is positive. Positive quadratic functions always concave upwards (in a “bowl-like” shape), creating a curve/minimum at the bottom.