Question

1) O valor de x do esquema abaixo (considere as retas a,b e c paralelas entre si)*​

Answer 1

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4/12 = x/21

12 . x = 4 . 21

12x = 84

x = 84/12

x = 7

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Att : MarcosPCV

Answer 2

$\large\boxed{\begin{array}{l} \underline{ \rm{teorema \: de \: tales}} \\ \\ \rm \dfrac{4}{12} = \dfrac{x}{21} \\ \\ \rm \: 12x = 21 \cdot4 \\ \\ \rm \: 12x = 84 \\ \\ \rm \: x = \dfrac{8 4 {}^{ } }{12} \\ \\ \boxed{ \boxed{ \rm{{x = 7 }}} }\end{array}}$