Answer:

Step-by-step explanation:
we know that
The formula to find the sum is equal to

where
a1 is the first term
an is the last term
n is the number of terms
In this problem we have



substitute the values in the formula

The correct answer for this problem is it has infinity solutions. Both equations equal up to t=5 -1/2
What do you need help with?
Answer:
12 and 12.5
Step-by-step explanation: