Question

8) Determinati x dacă:
a) 4.(x - 5) - 14 = 50;
c) [12 +3.(2x + 1)] = 24;
e) [(3x - 2).5-1): 2 + 5 = 7;
b) 3 + x [2 +3. (5 +2.3)] = 73;
d) 7+3 . [2 + 5.4. (3 + 2x)] = 313,
f) [(3x+8): 17-1] . 232 + 9 = 9;
g) [3+4·(6x - 1)]:47 +9 = 10;
1) 3+ 7. [45 - 3. (4x + 3)] = 3;
h) 2. [3+ 5. (2x - 1)] = 56,
j) 24 +5. [8 - 2. (x - 3)] = 24;

punctul inseamna ori(×)​

Answer 1

Explicație pas cu pas:

a) 4x-20-14=50

4x-34=50

4x=50+34

4x=84=>x=21

b) 3+x(2+33)=73

3+35x=73

35x=73-3

35x=70=>x=2

c) 12+6x+3=24

6x=24-15

6x=9=>x=9/6=3/2

d) 7+3×(2+60+40x)=313

7+3×(62+40x)=313

7+186+120x=313

193+120x=313

120x=313-193

120x=120=>x=1

e) [(15x-10)-1]:2+5=7

(15x-10-1):2+5=7

15x-11 × 1/2+5=7 (amplificam cu 2)

15x-11+ 10=14

15x=15=>x=1

f)[(3x+8)×1/17-1]×232+9=9

(3x/17+8/17-1)232+9=9

696x+1856-3944+153=153

696x=153-1856+3944-153

696x=2088

×=3

g) (3+24x-4):47+9=10

(24x-1)×1/47+9=10

24x/47-1/47+9=10

24x-1+423=470

24x=470+1-423

24x=48

x=2

h) 2(3+10x-5)=56

20x-4=56

20x=60

x=3

i)3+ 7×(45-12x-9)=3

3+7×(36-12x)=3

3+252-84x=3

-84x=3-255

84x=252

x=3

j)24+5×(8-2x+6)=24

24+5×(14-2x)=24

24+70-10x=24

-10x=24-24-70

-10x=-70

x=7