Question

Me ajudem b) (2x-3)×2=25
C) (x+1)×2-x=7
D(x-1)×2=x+5
E)(1-x)×2-3x=1
F)(3x-2)×2=(2-x)×2
G)(2x-1)×2=(x+5)×2
H)(x-2)×2+(x+1)×2=5

Answer 1

Resposta:

b) (2x-3)×2=25

$4x - 6 = 25 \\ 4x = 25 + 6 \\ 4x = 31 \\ x = \frac{31}{4}$

C) (x+1)×2-x=7

$2x + 2 - x = 7 \\ x + 2 - 7 = 0 \\ x - 5 = 0 \\ x = 5$

D(x-1)×2=x+5

$2x - 2 = x + 5 \\ 2x - 2 - x - 5 = 0 \\ x - 7 = 0 \\ x = 7$

E)(1-x)×2-3x=1

$2 - 2x - 3x = 1 \\ - 5x = 1 - 2 \\ - 5x = - 1 \times ( - 1) \\ 5x = 1 \\ x = \frac{1}{5}$

F)(3x-2)×2=(2-x)×2

$6x - 4 = 4 - 2x \\ 6x - 4 + 2x = 4 \\ 8x = 4 + 4 \\ 8x = 8 \div 8 \\ x = 1$

G)(2x-1)×2=(x+5)×2

$4x - 2 = 2x + 10 \\ 4x - 2 - 2x = 10 \\ 2x = 10 + 2 \\ 2x = 12 \div 2 \\ x = 6$

H)(x-2)×2+(x+1)×2=5

$2x - 4 + 2x + 2 = 5 \\ 4x - 2 = 5 \\ 4x = 5 + 2 \\ 4x = 7 \\ \\ x = \frac{7}{4}$