Question

Encontre o valor de x nas equações:
a) 7x + x + 2x = 80 b) 5.(x + 3) = 28
c) x + 5x = – 30 d) 3.x = –36
e) 2x + 4 = 68 f) 7x = x + 24
g) 10x – 4 = 8x + 6 h) 2.(x – 5) + 4.(x – 1) = 0
i ) x – x/7 = – 3

Answer 1

a) 7x+x+2x =80

10x=80

x=80/10

x=8

b) 5.(x+3) =28

5x + 15 = 28

5x= 28 -15

5x=13

x= 13/5

x=2,6

c) x+5x= - 30

6x =-30

x= -30/6

x= -5

d)3.x=-36

3x= -36

x= -36/3

x= -12

e)2x+4=68

2x= 68-4

2x= 64

x=64/2

x = 32

f)7x = x + 24

7x-x =24

6x=24

x= 24/6

x=4

g) 10x – 4 = 8x + 6

10x-8x=6+4

2x=10

x= 10/2

x=5

h) 2.(x – 5) + 4.(x – 1) = 0

2x-10+4x-4=0

2x+4x =10+4

6x= 14

x=14/6

x=2,3

i ) x – x/7 = – 3

-2x=-3/-7

-2x= - 0,4 (-1)

2x=o,4

x= 0,4/2

x=0,2

ufa