Question

Encontre a raiz da equações abaixo:


a) 20x - 4 = 5x


b) 4x = -8x + 36


c) x - 3 = 5


d) x + 2 = 7


e) 6x - 4 = 2x + 8


f ) 17x - 2 + 4 = 10 + 5x


g) 4x – 10 = 2x + 2


h) 5x + 6x – 16 = 3x + 2x - 4


i) x - 109 = 5


j) 15 = x +1​

Answer 1

Resposta:

a) x = 4/15 ou 0,2666...

b) x = 3

c) x = 8

d) x = 5

e) x = 3

f) x = 2/3 ou 0,666...

g) x = 6

h) x = 2

i) x = 114

j) 14 = x

Explicação:

a) 20x-4 = 5x

20x = 5x+4

20x-5x = 4

15x = 4

x = 4/15 ou 4÷15

4÷15 = 0,2666...

b) 4x = -8x+36

4x+8x = 36

12x = 36

x = 36÷12

x = 3

c) x-3 = 5

x = 5+3

x = 8

d) x+2 = 7

x = 7-2

x = 5

e) 6x-4 = 2x+8

6x-4-2x = 8

6x-2x = 8+4

4x = 12

x = 12÷4

x = 3

f) 17x-2+4 = 10+5x

17x-2+4-5x = 10

17x-5x = 10+2-4

17x-5x = 12-4

12x = 8

x = 8/12 ou 8÷12

8/12 = 8÷2/12÷2 = 4/6 = 4÷2/6÷2 = 2/3

8÷12 = 0,666...

g) 4x-10 = 2x+2

4x-10-2x = 2

4x-2x = 2+10

2x = 12

x = 12÷2

x = 6

h) 5x+6x-16 = 3x+2x-4

5x+6x-16-3x-2x = -4

5x+6x-3x-2x = -4+16

11x-3x-2x = -4+16

8x-2x = -4+16

6x = 12

x = 12÷6

x = 2

i) x-109 = 5

x = 5+109

x = 114

j) 15 = x+1

15-1 = x

14 = x