Given sequence:
-2,-7,-12 ,..
Unknown;
Find the sum of the first 20 terms = ?
Solution:
The sequence is -2,-7,-12 ,..
To find he sum of n-terms of a sequence, we use the expression below;
Sₙ = 
where n is the number of terms = 20
a is the first term = -2
d is the common difference= -7 - (-)2 = -5
Now input the parameters and solve;
Sₙ = 
Sₙ = 10(-4 + -5(19)) = 10(-99) = -990
The sum of the first 20 terms of the sequence is -990
Answer:
haha82829sjsjsm81kqqma s.sksjsjwnq9292929snakw999
Answer & Step-by-step explanation:
7). C = 44
8). S = 40
9). S = 40
10). T = 118
You can write in the comments if you want an explanation.
Hope this help ;)
Answer:
-5
Step-by-step explanation:
When you subtract a negative you end up adding it instead
Answer:
circumference
Step-by-step explanation:
it's a circle