Question

3) Resolva as seguintes equações: a) 3x + 2 =113 b) 3x - 2 = 3 c) 3x –9 = 0 d) - 2x -18 ​

Answer 1

a)

$3x+2=113\\\\3x+2-2=113-2\\\\3x=111\\\\\frac{3x}{3}=\frac{111}{3}\\\\x=37$

b)

$3x-2=3\\\\3x-2+2=3+2\\\\3x=5\\\\\frac{3x}{3}=\frac{5}{3}\\\\x=\frac{5}{3}$

c)

$3x-9=0\\\\3x-9+9=0+9\\\\3x=9\\\\\frac{3x}{3}=\frac{9}{3}\\\\x=3$

d)

Essa daqui esta muito diferente, mas tudo bem vamos la..

$-2x-18\\\\\\\mathrm{Reescrever\:}18\mathrm{\:como\:}2\cdot \:9\\=-2x-2\cdot \:9\\\\\\\mathrm{Fatorar\:o\:termo\:comum\:}-2\\=-2\left(x+9\right)$