Question

13 Rezolvați ecuațiile: a 3(x+5)-6(x - 2) = 4(x + 2) - 5(x-4) + 1;
b 2(2x + 7) + 3(x-1) = 6(x-3) + 18;
d 2x + 5+ 3(3x-1)=8(1-7x) + 2+ 3x;
c 15(x-1) + 4(2-3x) = 11 - 2(x + 4);
e 10(3-x) + 6(x + 3) =19 +7(2x-1).​

Answer 1

Răspuns:

a. 3(x+5)-6(x - 2) = 4(x + 2) - 5(x-4) + 1

3x + 15 - 6x + 12 = 4x + 8 - 5x + 20 + 1

3x - 6x - 4x + 5x = 1 + 20 + 8 - 12 - 15

- 2x = 2 ×(-1)

2x = - 2

x = 2/2

x = - 1

b. 2(2x + 7) + 3(x-1) = 6(x-3) + 18

4x + 14 + 3x - 3 = 6x - 18 + 18

4x + 14 + 3x - 3 = 6x

4x + 3x - 6x = - 3 - 14

x = - 11

c. 15(x-1) + 4(2-3x) = 11 - 2(x + 4)

15x - 15 + 8 - 12 x = 11 - 2x - 8

15x - 12x + 2x = - 8 + 11 - 8 + 15

5x = 10

x = 10/5

x = 2

d. 2x + 5+ 3(3x-1)=8(1-7x) + 2+ 3x

2x + 5 + 9x - 3 = 8 - 56x + 2 + 3x

2x + 9x + 56x - 3x = 2 + 8 + 3 - 5

64x = 8

x = 8/64

x = 1/8

e. 10(3-x) + 6(x + 3) =19 +7(2x-1)

30 - 10x + 6x + 18 = 19 + 14x - 7

- 10x + 6x - 14x = - 7 + 19 - 18 - 30

- 18x = - 36 ×(-1)

18x = 36

x = 36/18

x = 2