Question

Calcule o valor de x, nas sentenças abaixo:
a) x + 5 = 8 *
b) x + 6 = 10 *
c) x + 13 = 54 *
d) x + 27 = 42 *
e) 1 + x = 7 *
f) 4 + x = 9 *
g) 9 + x = 43 *
h) 18 + x = 54 *
i) x - 1 = 7 *
j) x - 4 = 9 *
k) x - 18 = 54
l) 8 - x = 7 *
Equações envolvendo multiplicação

2) Calcule o valor de x:
a) 2 . x = 14 *
b) 8 . x = 40 *
c) 6 . x = 18 *
d) 4 . x = 28 *
e) 15 . x = 60 *
f) 12 . x = 84 *
g) x . 5 = 45 *
h) x . 7 = 28 *
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Answer 1

1) a) x + 5 = 8

x = 8 - 5

x = 3

b) x + 6 = 10

x = 10 - 6

x = 4

c) x + 13 = 54

x = 54 - 13

x = 41

d) x + 27 = 42

x = 42 - 27

x = 15

e) 1 + x = 7

x = 7 - 1

x = 6

f) 4 + x = 9

x = 9 - 4

x = 5

g) 9 + x = 43

x = 43 - 9

x = 34

h) 18 + x = 54

x = 54 - 18

x = 36

i) x - 1 = 7

x = 7 + 1

x = 8

j) x - 4 = 9

x = 9 + 4

x = 13

k) x - 18 = 54

x = 54 + 18

x = 72

l) 8 - x = 7

-x = 7 - 8

-x = -1

x = 1

2) a) 2x = 14

x = 14/2

x = 7

b) 8x = 40

x = 40/8

x = 5

c) 6x = 18

x = 18/6

x = 3

d) 4x = 28

x = 28/4

x = 7

e) 15x = 60

x = 60/15

x = 4

f) 12x = 84

x = 84/12

x = 7

g) x × 5 = 45

5x = 45

x = 45/5

x = 9

h) x × 7 = 28

7x = 28

x = 28/7

x = 4