Question

Resolva as seguintes equações do 1 ° grau :
a)    3 . ( 2x -1 )  = 2 . ( x +1 ) +3
b)    3. ( x -1 ) –  2 . ( x -3 )  = 10   
c)    3x / 4 = 2 + 2x / 3  
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Answer 1

a)

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

b)

$\frac{3x}{4} = \frac{2 + 2x}{3} \\ \frac{9x}{12} = \frac{8 + 8x}{12} \\ 9x = 8 + 8x \\ 9x - 8x = 8 \\ x = 8$

c)

$3 \times (x - 1) - 2 \times (x - 3) = 10 \\ 3x - 3 - 2x + 6 = 10 \\ 3x - 2x = 10 + 3 - 6 \\ x = 13 - 6 \\ x = 7$