Answer:
195.25
Step-by-step explanation:
Consider geometric series S(n) where initial term is a
So S(n)=a+ar^1+...ar^n
Factor out a
S(n)=a(1+r+r^2...+r^n)
Multiply by r
S(n)r=a(r+r^2+r^3...+r^n+r^n+1)
Subtract S(n) from S(n)r
Note that only 1 and rn^1 remain.
S(n)r-S(n)=a(r^n+1 -1)
Factor out S(n)
S(n)(r-1)=a(r^n+1 -1)
The formula now shows S(n)=a(r^n+1 -1)/(r-1)
Now use the formula for the problem
Answer:

Step-by-step explanation:

Answer:
TU = 6
Step-by-step explanation:
Using the Segment Addition Postulate, we know that TU + UV = TV, and since UV = 6 and TV = 12, we know that TU + 6 = 12, therefore, TU = 6.
You just need to plug those expressions inside the formula: it doesn't matter if they're expressions involving a variable instead of plain numbers: the formula becomes

If you want, you can simplify it by expanding the square and then multiply the two parenthesis:

Answer:
558
Step-by-step explanation:
I can't say :>