Answer:

Try to solve the similtanious equation to find the first term and the common difference, then use that information to figure out the 80th term... Update me if you need further help ...
Answer:
-23/10 or-2 3/10
Step-by-step explanation:
Convert the decimal number to a fraction by placing the decimal number over a power of ten. Since there is
1
number to the right of the decimal point, place the decimal number over
10
1
(
10
)
. Next, add the whole number to the left of the decimal.
−
2
3
10
Perimeter = 26 Explanation: count the sides of the shape then add them all