Question

Resolva as equações do 1.° grau com uma incógnita, sendo u=q
A-)x-x/7=-6/7
B-) x/9+x/4=1/2
C-) x+12/3=x-5/4
D-) x+4/2-x+8/3=x-1/5

Answer 1

a) x - x/7 = -6/7

7x - x = -6

6x = -6

x = -6 : 6

x = -1

b) x/9 + x/4 = 1/2

MMC(9,4,2) = 36

4x/36 + 9x/36 = 18/36

4x + 9x = 18

13x = 18

x = 18/13

c) (x+12)/3 = (x-5)/4

MMC = 12

4(x+12) = 3(x-5)

4x + 48 = 3x - 15

4x - 3x = -15 - 48

x = - 63

d) (x+4)/2 - (x+8)/3 = (x-1)/5

MMC = 30

15(x + 4) - 10 (x+8) = 6 (x-1)

15x + 60 - 10x - 80 = 6x - 6

15x - 10x - 6x = -6 - 60 + 80

x = -66 + 80

x = 14