Question

8. Rezolvaţi ecuaţiile în mulțimea numerelor reale:
a) 4(x + 2) - 3x = -17; b) 6(x + 5) - 3x = 21; c) 11 - 3(x + 5) = 2x + 1;
d) 32 - 7(x - 5) = 3(x - 1); e) 4(x - 6) + 2x = 18; f) 4(x + 7) - 15 = 3x;
g) 14 – 8(x + 3) = 2x;
h) 6(x + 3) – 4 = 2x – 42;
i) 6(x - 4)+44 = 4(2x + 1) + 2x;
j) 5(2x - 3) - 4x = 3(x - 8) +63;
k) 3(x + 2) - 8 = 2(4x + 3) – 3x;
1) 4(3x + 2) + 3(2x + 3) = 7(2x + 5) + 28;
m) 4(x + 5) - 5(x + 3) = x – 5;
n)2(x + 3) – 3(2x + 1) = 8(2x - 1)-9;
0) 3(2x + 3) - 2(3x + 2) =-3(x + 2) + 2; p) -3x + 5 -- 4(x - 1) =-2(x + 1) - 24;
r) x - 15+ 3(x + 1) = 5(x - 2) + 11; s) 5(x + 2) - 2(2x + 3) = 34 – 5x.​

Answer 1

Răspuns:

a)

4( x+2) -3x = -17

4x + 8 -3x = -17

x +7 = -17

x = -17-7

x= -24

b)

6( x+5) -3x = 21

6x +30 -3x = 21

3x +30 =21

3x = 21-30

3x = -9

x = -3

c)

11-3( x+5) = 2x +1

11-3x- 15 = 2x +1

-3x - 2x = 1 -11 +15

- 5x = 5

x = -1

d)

32 -7 ( x-5) = 3( x-1)

32 -7x + 35 = 3x -3

-7x -3x = -3 -32 -35

-10 x = -70

x = 7

e)

4( x -6) +2x =18

4x-24+2x =18

6x = 18 +24

6x = 42

x= 42÷6

x = 7

f)

4( x +7) -15= 3x

4x +28 -15 =3x

4x-3x= -28 +15

x = -13

g)

14-8 ( x+3) = 2x

14 -8x -34 = 2x

-8x -2x = -14 +34

-10 x = 20

x = -2