Question

$\sqrt{x + 5} = x - 1$
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Answer 1

Resposta:

$\sqrt{ x + 5} = x - 1 \\ { (\sqrt{x + 5}) }^{2} = {(x - 1)}^{2} \\ x + 5 = {x}^{2} - 2x + 1 \\ {x}^{2} -3 x - 4 = 0 \\ \\ x = (3 + - \sqrt{9 -4(1)( - 4)} ) \div 2 \\ x = (3 + - \sqrt{9 + 16} ) \div 2 \\ x =( 3 + - \sqrt{25} ) \div 2 \\ x = (3 + - 5) \div 2 \\ \\ x = (3 + 5) \div 2 \\ ou \\ x = (3 - 5) \div 2 \\ \\ x = 4 \: ou \: x = - 1$