Question

5x elevado a 2 - 45 igual a 0

Answer 1

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${5x}^{2} - 45 = 0 \\ {5x}^{2} = 45 \\ {x}^{2} = \frac{45}{5} \\ {x}^{2} = 9 \\ x = \sqrt{9} \\ x = 3 \: \: \: o \: \: \: x = - 3$