Question

Rezolvati in numere naturale egalitatile: a) 3x+7=2(x-1)+10 b) 8x-3=2(x+2)+11 c) (5+4x) *(ori) 13-80=245 d) [(x-5):150+70]:71-1=0 e) 3*{2*[5*(3X+2)-4]-1}=933 f) {[(2x+3)*5+3]*2+7}:11+5=18 VA ROG SA MA AJUTATI!! :**

Answer 1

a)
3x+7=2(x-1)+10
3x+7=2x-2+10
3x+7=2x+8
3x-2x=8-7
x=1
b)
8x-3=2(x+2)+11
8x-3=2x+4+11
8x-3=2x+15
8x-2x=3+15
6x=18
x=18:6
x=3
c)
(5+4x)x13-80=245
65+52x=245+80
65+52x=325
52x=325-65
52x=260
x=260:52
x=5
d)
[(x-5):150+70]:71-1=0
[(x-5):150+70]:71=0+1
[(x-5):150+70]:71=1
[(x-5):150+70]=1x71
[(x-5):150+70]=71
[(x-5):150]=71-70
[(x-5):150]=1
x-5=1x150
x-5=150
x=150+5
x=155
e)
3x{2x[5x(3x+2)-4]-1}=933
{2x[5x(3x+2)-4]-1}=933:3
{2x[5x(3x+2)-4]-1}=311
{2x[5x(3x+2)-4]}=311+1
{2x[5x(3x+2)-4]}=312
{2x[5x(3x+2)]}=312+4
{2x[5x(3x+2)]}=316
[5x(3x+2)]=316:2
[5x(3x+2]=158
3x+2=158:5
3x+2=31,6
3x=31,6-2
3x=29,6
x=29,6:3
x=9,8(6)
f)
{[(2x+3)x5+3]x2+7}:11+5=18
{[(2x+3)x5+3]x2+7}:11=18-5
{[(2x+3)x5+3]x2+7}:11=13
{[(2x+3)x5+3]x2+7}=13x11
{[(2x+3)x5+3]x2+7}=143
{[(2x+3)x5+3]x2}=143-7
{[(2x+3)x5+3]x2}=136
{[(2x+3)x5+3]}=136:2
[(2x+3)x5+3]=68
[(2x+3)x5]=68-3
[(2x+3)x5]=65
(2x+3)=65:5
2x+3=13
2x=13-3
2x=10
x=10:2
x=5