Question

Resolva as equações:

A) x-x/2=1
B) x/3 + x/2=15
C)3x/2 - 5x=-7
D)x/2 + x/4 + x/2=4
E) 3/4x-1/2x=-2

(Deixem conta pfv)

Answer 1

A) x - x/2 = 1
 2x - x = 1.2
     x = 2

B) x/3 + x/2 = 15
  mmc: 6

2x + 3x = 15.6
5x = 90
x = 90/5
x = 18

C) 3x/2 - 5x = -7
3x - 2.5x = -7.2
3x - 10x = -14
-7x = -14
x = -14/-7
x = 2

D) x/2 + x/4 + x/2 = 4

mmc: 4

2x + x + 2x = 4.4
5x = 16
x = 16/5

E) 3/4x - 1/2x = -2

mmc: 4x

3 - 1.2 = -2.4x
3 - 2 = -8x
1 = -8x
x = -1/8

Espero ter ajudado.

Answer 2

a)

$x-\frac{x}{2} =1$

mmc = 2

$\frac{2x-x}{2} =1$

2x - x = 2

x = 2

b)
$\frac{x}{3} + \frac{x}{2} =15$

mmc = 6

$\frac{2x+3x}{6} =15$

2x + 3x = 6.15

5x = 90

x = 90/5

x = 18

c)

$\frac{3x}{2} -5x = -7$

mmc = 2

$\frac{3x-10x}{2} =-7$

3x - 10x = 2.(-7)

-7x = -14 (-1) multiplicar por -1 (a incógnita tem que ser positiva)

7x = 14

x = 14/7

x = 2

d)
$\frac{x}{2} + \frac{x}{4} + \frac{x}{2} =4$

mmc = 4

$\frac{2x+x+2x}{4} =4$

2x + x + 2x = 4.4

5x = 16

$x= \frac{16}{5}$

e)

$\frac{3}{4x} - \frac{1}{2x} =-2$

mmc = 4x

$\frac{3-2x}{4x} =-2$

3 - 2x = 4x.(-2)

3 - 2x = - 8x

- 2x + 8x = - 3

6x = -3

$x= \frac{-3}{6}$

simplificando a fração:

$x=- \frac{1}{2}$