Question

resolva as equacoes
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Answer 1

a) $21=3x$

$3x=21$

$x=\frac{21}{3}$

$x=7$

b) $84=6x$

$6x=84$

$x=\frac{84}{6}$

$x=14$

c) $\frac{x}{3}=7$

$x=7\cdot 3$

$x=21$

d) $\frac{x}{4}=-3$

$x=-3\cdot 4$

$x=-12$

e) $\frac{2x}{5}=4$

$2x=4\cdot 5$

$2x=20$

$x=\frac{20}{2}$

$x=10$

f) $\frac{2x}{3}=-10$

$2x=-10\cdot 3$

$2x=-30$

$x=\frac{-30}{2}$

$x=-15$

g) $\frac{3x}{4}=30$

$3x=30\cdot 4$

$3x=120$

$x=\frac{120}{3}$

$x=40$