Question

Calcular o valor de x na equação de 1°grau:

1) 5x=10-5
2) 5x+3x-10=20
3) 5x+3x-20+20-2x
4) 4x+15-2x= -5-2x
5) 30-5x+2x=100-2x
6) 5(x+10)=3x-100
7) 100=5 (12-x)
8) 12x +20+ 2x= 250+ 9x
​

Answer 1

Resposta:

1) 1

2) 30/8 = 3.75

3) 0

4) - 5

5) -70

6) -75

7) -8

8) 46

Explicação passo-a-passo:

1) 5x=10-5

resolver e isolar o x

5x = 5

x= 5/5

x=1

2) 5x+3x-10=20

agrupar e resolver

5x +3x = 20 +10

8x = 30

x=30/8 = 3.75

3) 5x+3x-20+20-2x

agrupar e resolver

5x + 3x - 2x -20 +20 = 0

5x + 3x - 2x = + 20 - 20

5x + 3x - 2x = 0

8x - 2x =

6x =0

x=0/6=0

4) 4x+15-2x= -5-2x

4x -2x + 2x = -5 -15

4x = -20

x=-20/4 = -5

5) 30-5x+2x=100-2x

-5x +2x + 2x = 100-30

-5x + 4x = 70

-1x = 70

x = 70/-1 = -70

6) 5(x+10)=3x-100

multiplica quem tá fora com quem tá dentro

5x + 50 = 3x - 100

5x -3x = -100 - 50

2x = - 150

x = -150 /2 = -75

7) 100=5 (12-x)

100 = 60 -5x

100 - 60 = - 5x

40 = - 5 x

-5x = 40

x = 40/-5 = -8

8) 12x +20+ 2x= 250+ 9x

​12x + 2x - 9x = 250 -20

5x = 230

x = 230/5 = 46

Espero ter ajudado!!