Question

14. Rezolvaţi în Z ecuațiile:
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) 2(x + 5) = -8(3x + 2) + 56;
f) 5(x-2) - 7(x + 3) + 35 = 0;
h) (-2x + 6)(x + 3) = 0.​

Answer 1

a) 9x-18=-63

9x=-45

x=-5

c) 8x+2=10x-14

-2x=-16

x=8

e) 1-4×(-5x+10)=21

1+20x-40=21

20x=60

x=3

g) x+3=0. x-7=0

x=-3. x=7

b) 5x+15=10x-10

-5x=-25

x=5

d) 2x+10=-24x-16+56

26x= 30

x=30/26 nu apartine lui Z

deci ec nu are solutii intregi

f) 5x-10-7x-21+35=0

-2x=-4

x=2

h) -2x+6=0. sau x+3=0

-2x=-6. x=-3

x=3