Question

como se faz essas contas:
a)3x+2(x-4)=5x-3(x-2)
b)5(x-4)-3=7(x-8)+33
c)7x-6(x-12)=12-21
d)8(3x-1)+4=6(2x-5)+9
e)3x-2(x-5)=7x-4(2x+1)
f)12x-4(3x-5)=13x-2(6x-20)

Answer 1

Resposta:

Explicação passo-a-passo:

a) 3x+2(x-4)=5x-3(x-2)

3x+2x-8=5x-3x+6

3x+2x-5x+3x=6+8

3x=14

x=$\frac{14}{3}$

b)5(x-4)-3=7(x-8)+33

5x-20-3=7x-56+33

5x-7x=56+33+3+20

-2x=112 (-1)

2x=-112

x=$\frac{-112}{2}$

x=-56

c)7x-6(x-12)=12-21

7x-6x+72=-9

7x-6x=-9-72

x=-81

d)8(3x-1)+4=6(2x-5)+9

24x-8+4=12x-30+9

24x-12x=-30+9+8-4

12x=-17

x=$\frac{-17}{12}$

e)3x-2(x-5)=7x-4(2x+1)

3x-2x+10=17x-8x-4

3x-2x-17x+8x=-4-10

-8x=-14 (-1)

8x=14

x=$\frac{14}{8}$ (/2)

x=$\frac{7}{4}$

f)12x-4(3x-5)=13x-2(6x-20)

12x-12x+20=13x-12x+40

12x-12x-13x+12x=40-20

-x=20 (-1)

x=-20