Answer:
-89
Step-by-step explanation:
The first term of the sequence is a1 = -12.
The common difference between terms is ...
d = -13 -(-12) = -1
The generic term is given by ...
an = a1 +d(n -1)
Then the 78th term is ...
a78 = -12 +(-1)(78 -1) = -12 -77
a78 = -89
Yes you have a good example.
x = number of cookies
2*x = total amount spent on cookies at $2 each
2x-3 = amount you pay after the $3 discount is applied one time for the entire order
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a more numeric example may be this
Lets say you bought 12 cookies, so x = 12
This means it costs 2*x = 2*12 = 24 dollars total if the discount doesnt apply
However, the 3 dollar discount is there, so the grand total is 24-3 = 21 dollars.
First, classify each line segments of triangle that are the same in both triangles.
RS = XU
RT = XW
ST = WU
Second, divide to find the scale ratio.
7.5/3 = 2.5
16/6.4 = 2.5
15/6 = 2.5
Since the scale ratios are identical, the triangles are similar.
Therefore, the answer is [ Yes, the sides are in the ratio 2:5 ]
Best of Luck!
