Question

VA ROG URGENT DAU COROANA
FARA RASPUNSURI AIUREA!!
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Answer 1

Explicație pas cu pas:

a)

$\dfrac{14x + 8y + 14z + 8t}{7x - 5y + 7z - 5t} = 4$

$\dfrac{14(x + z) + 8(y + t)}{7(x + z) - 5(y + t)} = 4$

$14(x + z) + 8(y + t) = 4 \times 7(x + z) - 4 \times 5(y + t)$

$8(y + t) + 20(y + t) = 28(x + z) - 14(x + z)$

$28(y + t) = 14(x + z) \iff 2(y + t) = (x + z)$

$\implies \dfrac{x + z}{y + t} = 2$

b)

$\dfrac{x}{y} = \dfrac{8y}{z} = \dfrac{z}{x} = \dfrac{x + 8y + z}{y + z + x} = \dfrac{x + y + z + 7y}{x + y + z} = 1 + \dfrac{7y}{x + y + z}$

$\implies (x + y + z) \in \mathcal{M}_{7}$

q.e.d.