Question

1)resolva as equaçoes em R:
a)5(x-2)-3(x+4)=6
b)7(x-1)-2(x-5)=x-5
c)x+x=1
4 3 2
d)5x-x+1=10
2

Answer 1

a)
5(x - 2) - 3(x + 4) = 6
5x - 10 - 3x - 12 = 6
2x - 22 = 6
2x = 6 +22
2x = 28
x = 28/2
x = 14

R.: x = 14
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b)
7(x - 1) - 2(x - 5) = x - 5
7x - 7 - 2x + 10 = x - 5
5x + 3 = x - 5
5x - x = - 5 - 3
4x = - 8
x = - 8/4
x = - 2

Resp.: x = - 2
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c)
x + x = 1
4    3    2
************************************************
mmc = 12

4,3,2: 2
2,3,1: 2
1,3,1: 3
1,1         =  2.2.3 = 4.3 = 12
**********************************************************
(continua)

3x + 4x =  6
    12       12  

7x = 6

Resp.:
x =  6
       7
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d)
5x - x + 1 = 10
         2

mmc = 2

10x - x + 1 = 20
       2            2

10x - x + 1 = 20
9x + 1 = 20
9x = 20 - 1
9x = 19
x = 19
       9

Resp.: x =  19
                    9