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Nutka1998 [239]
3 years ago
8

Find the sum. Homework: 9.4 arithmetic series

Mathematics
1 answer:
RUDIKE [14]3 years ago
5 0

Answer:

Step-by-step explanation:

a1 = 3(1) - 7 = - 4

a2 = 3(2) - 7 = -1

d = a2 - a1

d = -1 - (-4)

d = -1 + 4

d = 3

a60 = 3(60) - 7

a60 = 180 - 7

a60 = 173

n = 60

Sum = (a1 + a60) * n / 2

Sum = (-4 + 173) * 60/2

Sum = (169)*30

Sum = 5070

==================

Just to check, we'll use the second summation formula

d = 3

n = 60

a1 = -4

Sum = (2*a1 + (n - 1)*d )*n / 2

Sum = (2*(-4) + (60 -1)*3)* 60/2

Sum = (-8 + 59*3) * 30

Sum = (177 - 8)*30

Sum = 169 * 30

Sum = 5070

Same answer.

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Answer:

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6. ○ \displaystyle 43°

5. ○ \displaystyle ∠M ≅ ∠S

4. ○ \displaystyle octagon

3. ○ \displaystyle squares

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Step-by-step explanation:

7. Everything is in correspondence with each other, so just follow the pattern in the order the they were originally.

6. All angles correspond with each other, so just follow the pattern.

5. All segments and angles correspond with each other, so just follow their patterns.

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3. In a previous lesson, we confirmed that <em>all squares </em><em>are</em><em> </em><em>rectangles</em><em> </em>because it is a quadrilateral with four right angles.

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I am joyous to assist you anytime.

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Answer:

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Step-by-step explanation:

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x + 569° =720°

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Step-by-step explanation:

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