Question

Rezolvați în mulțimea numerelor întregi ecuatiile:a) |2x+7|=15 b) |x-4|+5=7 c) ||2x-5|-7=10 d)2[3|2x+5|-4]-7=3
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Answer 1

|2x+7|=15 =>

1. 2x + 7 = 15

2x = 8

x = 4

2. 2x + 7 = -15

2x = -22

x = -11

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|x-4|+5=7

|x-4| = 2 =>

1. x-4 = 2

x = 6

2. x-4 = -2

x = 2

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|2x-5|-7=10

|2x-5| = 17 =>

1. 2x - 5 = 17

2x = 22

x = 11

2. 2x - 5 = -17

2x = -12

x = -6

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2[3|2x+5|-4]-7=3

6|2x+5|-8 - 7 = 3

6|2x+5|-8= 10

6|2x+5| = 18

|2x+5| = 3 =>

1. 2x + 5 = 3

2x = -2

x = -1

2. 2x + 5 = -3

2x = -8

x = -4