1. Assignment:
1-->Set 73 (odds) - Due Wednesday (4/4)
2-->Test #10 - Thursday (4/5)
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2. Lesson 73 Warm-Up:
1) 38% of the students went to the Cards game. If there were 150
students in all, how many did not go to the Cards game?
2) Graph: y = 2x - 2 Does the graph show direct variation? Why or
why not?
3) Graph: y = 1/2x Does the graph show direct variation? Why or
why not?
4) What is the tax on a $85.97 purchase if the rate is 8%?
5) Solve: 2(x + 7) - 4 = 24
[show all steps!]
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3. Lesson 73:
fyi...when we have a sequence of numbers, we can write the
"rule" as a formula.
number of term (n) 1 2 3 4 5
value of term (a) 3 6 9 12 15
The rule-->multiply by 3
The formula--> an = 3n
So...to find the 7th term, plug in 7 for both "n's"
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4. Some sequences have special names...
1, 3, 6, 10, 15, ...
This is called triangular numbers because...
The formula for this sequence is: an = n(n + 1)
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100th term-->
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5. Lesson 73 Examples:
A) What is the 7th term in this sequence:
1, 4, 9, 16, ...
B) Using the formula an = 5n - 2 what would be the 10th term?
C) Which formula below generates the terms of this sequence?
0, 3, 8, 15
A. an = n - 1 B. an = 2n - 1 C. an = n2 - 1
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6. D) What are the first 4 terms in the sequence generated by
the formula: an = n2 + 2n + 1
E) What is the 20th triangular number?
F) Find the 20th term for the following sequence:
an = 2n - 3
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