Question

11. Rezolvaţi în Z ecuatiile:
a) 9(x - 2) = -63;
c)2(4x + 1) - 2(5x - 7);
e) 1 - 4.(-5. (x - 2)]=21;
g) (x + 3)(x - 7)=0;
b) 5(x + 3) = 2(5x - 5);
d) 24-x + 5) --8(3x + 2) + 56;
1) 5(x-2) - 7(x+3) + 350,
h) (-2x + 6)(x + 3) = 0.​

Answer 1

Răspuns:

a) 9(x-2)= - 63 =>

9x-18= - 63 =>

9x= - 63+18 =>

9x= -45 =>

x= - 45:9 =>

x= -5.

c) 2(4x+1)-2(5x-7) =

8x+2-10x+14=0 =

8x-10x= - 2-14 =

-2x= - 16 =

x= - 16: - 2

x= 8

e) 1-4(5(x-2))=21 =

1-4(5x-10)= 21 =

1-20x+40= 21 =

1+40-21= +20x =

41-21= 20x =

20= 20x =

x=20:20 =

x= 1.

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

5x+15=10x-10 =

5x-10x= - 15-10 =

-5x= - 25 =

x= - 25: - 5 =

x= 5.