Question

resolva as equações
a)3×–7=2x+5
b)7x+8=4x–10
c)2x–4–8=4
e)3x=x+1+7
f)360+36x=30x
g)2x+5–5x=–1
h)5+6x=5x+2.
i)x+2x–1–3=x
j)–3x+10=2x+8+1 ​

Answer 1

Resposta:

a)x = 12

b)x = -6

c)x = 8

e)x=4

f)x=-60

g)2=x

h)x=-3

i)x=2

j)0,2 ou 1/5 = x

Explicação:

a)3x-7 = 2x+5

3x-7-2x = 5

3x-2x = 5+7

x = 12

b)7x+8 = 4x-10

7x+8-4x = -10

7x-4x = -10-8

3x = -18

x = -18÷3

x = -6

c)2x-4-8 = 4

2x = 4+4+8

2x = 8+8

2x = 16

x = 16÷2

x = 8

e)3x = x+1+7

3x-x = 1+7

2x = 8

x = 8÷2

x = 4

f)360+36x = 30x

36x = 30x-360

36x-30x = -360

6x = -360

x = -360÷6

x = -60

g)2x+5-5x = -1

5 = -1-2x+5x

5+1 = -2x+5x

6 = 3x

6÷3 = x

2 = x

h)5+6x = 5x+2

5+6x-5x = 2

6x-5x = 2-5

x = -3

i)x+2x-1-3 = x

x+2x = x+1+3

x+2x-x = 1+3

3x-x = 1+3

2x = 4

x = 4÷2

x = 2

j)-3x+10 = 2x+8+1

10 = 2x+8+1+3x

10-8-1 = 5x

2-1 = 5x

1 = 5x

1/5 ou 1÷5 = x

1÷5 = 0,2