“Line graphs are useful in that they show data variables and trends very clearly and can help to make predictions about the results of data not yet recorded. They can also be used to display several dependent variables against one independent variable.”
“With a line graph, it is fairly easy to make predictions because line graphs show changes over a period of time. You can look at past performance in a line graph and make a prediction about future performance.”
Answer: Choice A
S9 = (9/2)*(2+26)
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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
A = L * W
W = L - 5
these are in inches...
length width area
10 5 50 in^2
9 4 36 "
8 3 24 "
7 2 14 "
6 1 6 "