Answer:
(d-3)/2
Step-by-step explanation:
Difference is subtraction
(d-3)/2
Answer: Choice A
S9 = (9/2)*(2+26)
===============================================
The formula is
Sn = (n/2)*(a1+an)
where
Sn = sum of the first n terms (nth partial sum)
n = number of terms
a1 = first term
an = nth term
In this case,
n = 9
a1 = 2 (plug in n = 1 into the formula an = 3n-1 and simplify)
an = a9 = 26 (plug n = 9 into the formula an = 3n-1 and simplify)
So,
Sn = (n/2)*(a1+an)
S9 = (9/2)*(2+26)
will help us find the sum of the first 9 terms of this arithmetic sequence
The second option ! 2.54 - 2.3 = 0.24
Answer:
x = - 2 or x = 4
Step-by-step explanation:
the expression inside the absolute value can be positive or negative
Removing the bars and solve x - 1 = ± 3
x - 1 = - 3 or x - 1 = 3
x - 1 = - 3 ( add 1 to both sides ) ⇒ x = - 2
x - 1 = 3 ( add 1 to both sides ) ⇒ x = 4
I think it would best be displayed as a line plot.
