Question

Resolva as equações incompletas

a) 4x²= 81

b) x²= 625
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Answer 1

Resposta:

$4 {x}^{2} = 81 \\ {x}^{2} = \frac{81}{4} \\ \\ {x}^{2} = \frac{9}{2} \\ x = + - \frac{9}{2} \\ \\ \\ x = - \frac{9}{2} \\ \\ x = \frac{9}{2}$

${x}^{2} = 625 \\ x = + - \sqrt{625 } \\ \\ x = + - 25 \\ \\ x = - 25 \\ \\ x = 25$