Question

Preciso disso pra AGORA!Por favor me ajudem!
1-Determine o valor das incógnitas das equações a seguir:
a)3x-(x+1)=-x+1
b)2x+4.(38-x)=136
c)2(2x+5)-(4x-9)=3(3-4x)
d)9x-20=8(x-1)

Answer 1

$a) \\ \\ 3x - (x + 1) = -x + 1 \\ \\ 2x - 1 = -x + 1 \\ \\ 2x + x = 1 + 1 \\ \\ 3x = 2 \\ \\=> x = \dfrac{2}{3}$

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$b) \\ \\ 2x + 4 (38 - x) = 136 \\ \\ 2x + 152 - 4x = 136 \\ \\ -2x + 152 = 136 \\ \\ -2x = 136 - 152 \\ \\ -2x = - 16 (-1) \\ \\ 2x = 16 \\ \\ x = \dfrac{16}{2} \\ \\ => x = 8$

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$c) \\ \\ 2(2x + 5) - (4x - 9) = 3(3 - 4x) \\ \\ 4x + 10 - (4x - 9) = 9 - 12x \\ \\ 4x + 10 - 4x + 9 = 9 - 12x \\ \\ 19 = 9 - 12x \\ \\ 12x = 9 - 19 \\ \\ 12x = -10 \\ \\ x = - \frac{10}{12} \\ \\=> x = - \frac{5}{6}$

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$d) \\ \\ 9x - 20 = 8(x - 1) \\ \\ 9x - 20 = 8x - 8 \\ \\ 9x - 8x = -8 + 20 \\ \\=> x = 12$