Answer:
950
Step-by-step explanation:
The common difference is 4, so the general term can be written:
... an = 14 + 4(n -1)
The value of n for the last term is ...
... 86 = 14 + 4(n -1) . . . . . the computation for the last term, 86
... 72 = 4(n -1) . . . . . . . . . subtract 14
... 18 = n -1 . . . . . . . . . . . divide by 4
... 19 = n . . . . . . . . . . . . . add 1
Your series has 19 terms. The first term is 14 and the last is 86, so the average term is (14+86)/2 = 50. Since there are 19 terms, the sum of them is ...
... 19×50 = 950
Answer: 
Step-by-step explanation:
I believe that the answer is 120 marbles.<span />
Answer:
(x - 6)² = 18
Step-by-step explanation:
(x - 6)² = 18
x² - 12x + 36 = 18
x² - 12x + 18
Answer:
x = -11
Step-by-step explanation:
Add 9 to both sides of the equation
3 − 9 = −42
3 − 9 + 9 = −42 + 9
Simplify
Add the numbers
3 = −33
Divide both sides of the equation by the same term
3 = −33
3/3 = −33/3
Simplify
Cancel terms that are in both the numerator and denominator
Divide the numbers
= −11