Question

1- resolva as equações
A) X - 5 = 8?
B) 3 x = 15?
C) 5 x = 20?
D) 3 x + 10 = 2 x + 12?
E) 4x - 5 = - 6 x + 2?
F) 10 x + 10 = 3 x + 8?
G) 9 x - 1 = 2?
H) 3 x + 4 = 2 x - 1?
I) 6 x - 5 = 8 x + 2?
J) 3 x + 6 = x - 1?
K) 4 x + 9 = + 5?
L) 5 x - 6 = 2 x + 7?
M) 9 x + 6 = 7 x + 1?
N) 3 x + 1 = 12?

Answer 1

A) X - 5 = 8

X = 8 + 5 .: X = 13

B) 3X = 15

3X = 15 .: X = 15/3 = 5

C) 5 x = 20

X = 20/5 = 4

D) 3 x + 10 = 2x + 12

3x - 2x = 12 - 10

x = 2

E) 4x - 5 = - 6 x + 2

4x + 6x = 2 + 5

10x = 7

x = 7/10 = 0,7

F) 10 x + 10 = 3 x + 8?

10x - 3x = 8 - 10

7x = -2

x = -2/7

G) 9 x - 1 = 2

9x = 2 + 1

9x = 3

x = 3/9

x = 1/3

H) 3 x + 4 = 2 x - 1

3x - 2x = -1 -4

x = -5

I) 6 x - 5 = 8 x + 2?

6x - 8x = 2 + 5

- 2x = 7

x = 7/ -2 = -3,5

J) 3 x + 6 = x - 1

3x - x = -1 -6

2x = -7

x = -7/2 = -3,5

K) 4 x + 9 = + 5

4x = 5 - 9

x= -4/4 = -1

L) 5 x - 6 = 2 x + 7

5x - 2x = 7 + 6

3x = 13

x = 13/3

M) 9 x + 6 = 7 x + 1

9x - 7x = 1 - 6,

2x = -5

x = -5/2 = -2,5

N) 3 x + 1 = 12

3x = 12-1

x = 11/3