Question

Rezolvați in Z ecuațiile:

a)5x +11=66;
b)x:(-3)=-12;
c)120:x=-30;
d)x•(-7)=14;
e)35-x=23;
f)4-3x=-35;
g)5x=-30;
h)14+2x=-26;
i)25+5x=0;
j)12x=-8+4x;
k)7x-6=x;
l)-6+x=-x;

va rog!!​

Answer 1

Răspuns:

Explicație pas cu pas:

A rezolva o ecuatie inseamna a afla valoarea necunoscutei ,

aici notata cu x.

a) 5x+11 = 66 <=> 5x = 66-11 <=> 5x = 55 => x = 55:5 => x = 11 ∈Z

b) x:(-3) = -12 <=> x = (-12)·(-3) <=> x = 36 ∈Z

c) 120:x = -30 <=> 120 = -30·x => x = 120:(-30) => x = -4 ∈Z

d) x·(-7) = 14 <=> x = 14:(-7) => x = -2 ∈Z

e) 35-x = 23 <=> 35-23 = x => x = 12 ∈Z

f) 4-3x = -35 <=> 4+35 = 3x <=> 39 = 3x => x = 39:3 => x = 13 ∈Z

g) 5x = -30 => x = -30:5 => x = -6 ∈Z

h) 14+2x = -26 <=> 2x = -26-14 <=> 2x = -40 => x = (-40):2 => x = -20 ∈Z

i) 25+5x = 0 <=> 5x = -25 => x = -25 :5 => x = -5 ∈Z

j) 12x = -8+4x <=> 12x-4x = -8 <=> 8x = -8 => x = -8:8 => x = -1 ∈Z

k) 7x-6 = x <=> 7x-x = 6 <=> 6x = 6 => x = 6:6 => x = 1 ∈Z

l) -6+x = -x <=> -6 = -x-x <=> -6 = -2x => x = (-6):(-2) => x = 3 ∈Z