Question

Alguém me ajuda???
Preciso só da 1, 2, 3, 4 e 5

Answer 1

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1)

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A

40/100 = 32/x

40x = 3.200

x = 3200/40

x = 80

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B

5,4/x = 4,5/3

4,5x = 5,4 × 3

4,5x = 16,2

x = 16,2/4,5

X = 3,6

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2)

21/49 = 27/x

21x = 1323

x = 1323/21

x = 63 ← DF

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3)

5/8 = x/4

20 = 8x

x = 20/8

x = 2,5

2,5/4 = 2,75/y

2,5y = 11

y = 11/2,5

y = 4,4

2,5 + 4,4

6,9 ← Resposta final

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4)

y = 45 - x

5/13 = x/(45 - x)

225 - 5x = 13x

225 = 5x + 13

225 = 18x

x = 225/18

x = 12,5

x + y = 45

12,5 + y = 45

y = 45 - 12,5

y = 32,5

y - x

32,5 - 12,5

20 ← Resposta final

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5)

x/(x + 2l = (2x + 4)/25

25x = (x + 2)(2x + 4)

25x = (x . 2x) + 4x + 4x + 8

25x = 2x² + 8x + 8

2x² - 17x + 8 = 0

x = (17 ± √289 - 4(2)(8))/2

x = (17 ± √225l/2

x = (17 ± 15)/2

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x = 32/2 = 16

x = 2/2 = 1

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S = { 16 ; 1 }

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Att: MarcosPCV