Răspuns :
deci:
[tex]( \frac{5}{7} - \frac{5}{7x}) \div \frac{10}{14} = \frac{42}{21} \\ \frac{5x - 5}{7x} \times \frac{14}{10} = \frac{6}{3} \\ \frac{5(x - 1)}{7x} \times \frac{ {7}{5} = 2 \\ \frac{x - 1}{x} = 2 \\ 2x = x - 1 \\ 2x - x = - 1 \\ x = - 1[/tex]
sper că te-am ajutat ;)
[tex]( \frac{5}{7} - \frac{5}{7x}) \div \frac{10}{14} = \frac{42}{21} \\ \frac{5x - 5}{7x} \times \frac{14}{10} = \frac{6}{3} \\ \frac{5(x - 1)}{7x} \times \frac{ {7}{5} = 2 \\ \frac{x - 1}{x} = 2 \\ 2x = x - 1 \\ 2x - x = - 1 \\ x = - 1[/tex]
sper că te-am ajutat ;)
( 5 / 7 - 5 / 7 x ) : 10 / 14 = 42 / 21 → am simplificat pe 10 si 14 prin 2
( 5 x / 7 x - 5 / 7 x ) × 7 / 5 = 2
→ am dat factor comun pe 5 / 7 ( in paranteza rotunda)
( x - 1 ) / x · 5 / 7 × 7 / 5 = 2
→ se reduc 5 cu 5 si 7 cu 7
( x - 1 ) / x = 2
2 x = x - 1
2 x - x = - 1
x = - 1
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( 5 / 7 - 5 x / 7 ) : 5 / 7 = 2
5 / 7 × ( 1 - x ) × 7 / 5 = 2
1 - x = 2 ⇒ - x = 2 - 1 ⇒ x = - 1