Question

Alguém pode me ajudar com essas equações por favor

Answer 1

a) 21x - 17 = 109

21x = 109 + 17

21x = 126

x = 126 ÷ 21

x = 6

b) 73x + 100 = 53x

73x = 53x - 100

73x - 53x = -100

20x = -100

x = -100 ÷ 20

x = -5

c) 1,7 + 2,5x = 4,2

2,5x = 4,2 - 1,7

2,5x = 2,5

x = 2,5 ÷ 2,5

x = 1

d) 23x - 22 = 19x + 6

23x - 19x - 22 = 6

23x - 19x = 6 + 22

4x = 28

x = 28 ÷ 4

x = 7

e) 12x - 16 = -21 + 10x

12x - 10x - 16 = -21

12x - 10x = -21 + 16

2x = -5

x = -5/2

f) 1,9x - 3,6 = x - 10,8

1,9x - x - 3,6 = -10,8

1,9x - x = -10,8 + 3,6

0,9x = -7,2

x = -7,2 ÷ 0,9

x = -8

g) 10 (x + 1) - 5 (x - 2) = 70

10x + 10 - 5 ( x - 2) = 70

10x + 10 - 5x + 10 = 70

5x + 10 + 10 = 70

5x + 20 = 70

5x = 70 - 20

5x = 50

x = 50 ÷ 5

x = 10

h) 5 (x + 2) - 13 = 2 (3x -1)

5x + 10 - 13 = 2 (3x - 1)

5x + 10 - 13 = 6x - 2

5x - 3 = 6x - 2

5x - 6x - 3 = -2

5x - 6x = -2 + 3

-x = 1 × (-1)

x = -1

i) 7 (2 + x) = 5 ( x - 1,2) + 35

14 + 7x = 5 (x - 1,2) + 35

14 + 7x = 5x - 6 + 35

14 + 7x = 5x + 29

7x - 5x = 29 - 14

2x = 15

x = 15/2

j) 3 (x + 1) - 2 (x - 1) = - (x + 5)

3x + 3 - 2 (x - 1) = - (x + 5)

3x + 3 - 2x + 2 = - (x + 5)

3x + 3 - 2x + 2 = -x - 5

x + 3 + 2 = -x - 5

x + 5 = - x - 5

x + x = - 5 - 5

2x = -10

x = -10 ÷ 2

x = -5