Question

Encontre o valor da incógnita x em cada equação utilizando o processo algébrico (ou seja, deve apresentar a conta):
a) 3x + 2 = 14
b)2x - 3 = 7
c)3x = 18
d)2x +2 = 8
e)2x + 2 = 8
f)3x - 2 = 7
g)3x + 26 = -1
h)3x -4 =11
i)3x+7=x+3
k)11x+1=12
L)2x+2=12
m)12x=48
n)2x+6=x+18
o)5x-3=2x+9
p)3x-5=13
q)3x+5=2
r)-3x=-6
s)4x+6x=12-2x
t)3x=-x+24

Answer 1

Resposta:

a) 3x + 2 = 14

$3x + 2 - 14 = 0 \\ 3x - 12 = 0 \\ 3x = 12 \div (3) \\ x = 4$

b)2x - 3 = 7

$2x - 3 - 7 = 0 \\ 2x - 10 = 0 \\ 2x = 10 \div (2) \\ x = 5$

c)3x = 18

$3x = 18 \div (3) \\ x = 6$

d)2x +2 = 8

$2x + 2 - 8 = 0 \\ 2x - 6 = 0 \\ 2x = 6 \div (2) \\ x = 3$

e)2x + 2 = 8

$2x + 2 - 8 = 0 \\ 2x - 6 = 0 \\ 2x = 6 \div (2) \\ x = 3$

f)3x - 2 = 7

$3x - 2 - 7 = 0 \\ 3x - 9 = 0 \\ 3x = 9 \div (3) \\ x = 3$

g)3x + 26 = -1

$3x + 26 + 1 = 0 \\ 3x + 27 = 0 \\ 3x = - 27 \div (3) \\ x = - 9$

h)3x -4 =11

$3x - 4 - 11 = 0 \\ 3x - 15 = 0 \\ 3x = 15 \div (3) \\ x = 5$

i)3x+7=x+3

$3x + 7 - x - 3 = 0 \\ 2x + 4 = 0 \\ 2x = - 4 \div (2) \\ x = - 2$

k)11x+1=12

$11x + 1 - 12 = 0 \\ 11x - 11 = 0 \\ 11x = 11 \div (11) \\ x = 1$

L)2x+2=12

$2x + 2 - 12 = 0 \\ 2x - 10 = 0 \\ 2x = 10 \div (2) \\ x = 5$

m)12x=48

$12x = 48 \div (12) \\ x = 4$

n)2x+6=x+18

$2x + 6 - x - 18 = 0 \\ x - 12 = 0 \\ x = 12$

o)5x-3=2x+9

$5x - 3 - 2x - 9 = 0 \\ 3x - 12 = 0 \\ 3x = 12 \div (3) \\ x = 4$

p)3x-5=13

$3x - 5 - 13 = 0 \\ 3x - 18 = 0 \\ 3x = 18 \div (3) \\ x = 6$

q)3x+5=2

$3x + 5 - 2 = 0 \\ 3x + 3 = 0 \\ 3x = - 3 \div (3) \\ x = - 1$

r)-3x=-6

$- 3x = - 6 \times ( - 1) \\ 3x = 6 \div (3) \\ x = 2$

s)4x+6x=12-2x

$4x + 6x - 12 + 2x = 0 \\ 12x - 12 = 0 \\ 12x = 12 \div (12) \\ x = 1$

t)3x=-x+24

$3x + x - 24 = 0 \\ 4x - 24 = 0 \\ 4x = 24 \div (4) \\ x = 6$