Question

resolva as seguintes equações do 1° grau:

a) 2 x + 3 x + 9 = 8 (6 - x)
b) 4 (x - 10) - 2 (x - 5) = 0
c) 3 (2 x + 3) - 4 (x - 1) = 3
d) 7 (x - 1) - 2 (x - 5) = x - 5
e) 2 (3 - x) = 3 (x - 4) + 15
f) 3 (5 - x) - 3 (1 - 2 x) = 42

Answer 1

Resposta:

Explicação passo a passo:

a) 2 x + 3 x + 9 = 8 (6 - x)

5x+9=8*6-8x

5x+9=384-8x

5x+8x=384-9

13x=375

x=375/13

x=28,84

b) 4 (x - 10) - 2 (x - 5) = 0

4*x-4*10-2*x+2*5=0

4x-40-2x+25=0

4x-2x=0+40-25

2x=40-25

x=15/2

x=7,5

c) 3 (2 x + 3) - 4 (x - 1) = 3

3*2x+3*3-4*x+4*1=3

6x+9-4x+4=3

6x-4x=3-9-4

2x= -10

x= -10/2

x= -5

d) 7 (x - 1) - 2 (x - 5) = x - 5

7*x-7*1-2*x+2*5=x-5

7x-7-2x+25=x-5

7x-2x-x= -5+7-25

4x= 2-25

4x= -23

x= -23/4

x= -5,75

e) 2 (3 - x) = 3 (x - 4) + 15

2*3-2*x=3*x-3*4+15

6-2x=3x+12+15

-2x-3x=12+15-6

-5x=27-6

x= 21/-5

x= -4,2

f) 3 (5 - x) - 3 (1 - 2 x) = 42

3*5-3*x-3*1+3*2x=42

15-3x-3+6x=42

-3x+6x=42-15+3

3x=42-18

x= 24/3

x=8