Question

Va rog repede! Dau coroana!​

Answer 1

Răspuns:

135

Explicație pas cu pas:

$\dfrac{5 \cdot 9^{73} + 5 \cdot 9^{73}}{10 \cdot 9^{71}} = \dfrac{9x}{15} \iff \dfrac{2 \cdot 5 \cdot 9^{73}}{10 \cdot 9^{71}} = \dfrac{3x}{5}$

$\dfrac{10 \cdot 9^{73}}{10 \cdot 9^{71}} = \dfrac{3x}{5} \iff 9^{73-71} = \dfrac{3x}{5}$

$9^{73-71} = \dfrac{3x}{5} \iff 9^{2} = \dfrac{3x}{5}$

$81 = \dfrac{3x}{5} \iff x = \dfrac{5 \cdot 81}{3}$

$\implies \bf x = 135$