Question

5x = 0 - 20
3x = 20 - 5
4x = 30 + 10 -
5x = -20
3x = 15
4x = 40
1
-20
15
X=
3
40
X=
4
5
x = 5
x = 10
X = -4
Exercícios:
1) Resolva as expressões algébricas abaixo:
a) 3x + 7 = 10
d) 2x - 20 = 10
g) 6x - 30 = 0
b) 4x + 8 = 0
e) 3x - 9 = 0
h) 10x + 100 = 200
615x+20-1
c) 5x + 20 = 10
f) 4x - 16 = 16
i) 7x - 21 = 14​

Answer 1

Opaa, vamos lá!

a) 3x + 7 = 10

3x = 10 - 7

3x = 3

x = 3/3

x = 1

d) 2x - 20 = 10

2x = 10 + 20

2x = 30

x = 30/2

x = 15

g) 6x - 30 = 0

6x = 0 + 30

6x = 30

x = 30/6

x = 5

b) 4x + 8 = 0

4x = 0 - 8

4x = -8

x = -8/4

x = -2

e) 3x - 9 = 0

3x = 0 + 9

3x = 9

x = 9/3

x = 3

h) 10x + 100 = 200

10x = 200 - 100

10x = 100

x = 100/10

x = 10

615x+20-1

615x + 20 - 1 = 0 (vou entender como igual a 0)

615x = 1 - 20

615x = - 19

x = - 19/615

x = - 0,111...

c) 5x + 20 = 10

5x = 10 - 20

5x = - 10

x = - 10/5

x = - 2

f) 4x - 16 = 16

4x = 16 + 16

4x = 32

x = 32/4

x = 8

i) 7x - 21 = 14

7x = 14 + 21

7x = 35

x = 35/7

x = 5

Espero ter ajudado :)