Question

Me ajudem please!!!!
5(elevado a 2x)+20.5(elevado a x)-125=0

Answer 1

Fazendo $5^{2x} = y$

$5^{2x} + 20.5^{x} = 125\\\\ 5^{2x} + 4.5^{2x} =125 \\\\ y + 4y = 125 \\\\ 5y = 125 = \\\\ y = 25$

$5^{2x} = 25 \\\\ 5^{2x} = 5^2 \\ \\ 2x = 2 \\\\ x = 1$

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