Question

i) 18
3x=20

m) 18 18
3x 3x=6

n)40= 2x 2x
10 10

o) 9= 36 36
x x

Answer 1

Resposta:

l) x = 3/10

$l)\ \boxed{x=\dfrac{3}{10}}$

m) x = (3√6)/2

$m)\ \boxed{x=\dfrac{3\sqrt{6}}{2}}$

n) x = 10√10

$n)\ \boxed{x=10\sqrt{10}}$

o) x = 12

$o)\ \boxed{x=12}$

Explicação passo-a-passo:

$l)\ \dfrac{18}{3x}=20\\\\3x.20=18\\\\3x=\dfrac{18}{20}\\\\x = \dfrac{\dfrac{18}{20}}{3} = \dfrac{18}{20}}.\dfrac{1}{3} = \dfrac{6}{20}}.\dfrac{1}{1}= \dfrac{3}{10}\\\\\boxed{x =\dfrac{3}{10}\\\\}$

$m)\ \dfrac{18}{3x}\ .\ \dfrac{18}{3x} = 6\\\\\dfrac{18^2}{9x^2}=6\\\\54x^2=18^2\\\\x^2= \dfrac{18^2}{54}\\\\\\x=\sqrt{ \dfrac{18^2}{54}} = \dfrac{\sqrt{18^2}}{\sqrt{2^2.6}}=\dfrac{18}{2\sqrt{6}}=\dfrac{9}{\sqrt{6}}=\dfrac{9}{\sqrt{6}}\ .\ \dfrac{\sqrt{6}}{\sqrt{6}}=\dfrac{9\sqrt{6}}{6}=\dfrac{3\sqrt{6}}{2}\\\\\\m)\ \boxed{x=\dfrac{3\sqrt{6}}{2}}$

$n)\ 40=\dfrac{2x}{10}\ .\ \dfrac{2x}{10}\\\\40=\dfrac{4x^2}{10^2}\\\\4x^2 = 40\ .\ 10^2\\\\x^2 = \dfrac{40\ .\ 10^2}{4} = 10\ .\ 10^2\\\\x=\sqrt{10\ .\ 10^2} = 10\sqrt{10}\\\\n)\ \boxed{x=10\sqrt{10}}$

$o)\ 9=\dfrac{36}{x}\ .\ \dfrac{36}{x}\\\\9 = \dfrac{36^2}{x^2}\\\\x^2=\dfrac{36^2}{3^2}\\\\x=\sqrt{\dfrac{36^2}{3^2}} = \dfrac{36}{3} = 12\\\\\\o)\ \boxed{x=12}$

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