Question

Resolva as seguintes equações do segundo grau

2x² = 7x
2x² = 8x

Answer 1

$2 x^{2} =7x\\2 x^{2} -7x=0\\x(2x-7)=0\\\\x'=0~~~~~~~~~~~~~~~~~~2x-7=0\\ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~2x=7\\ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~x''=7/2\\\\ \boxed{S=\{0, \frac{7}{2}\}}$


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$2 x^{2} =8x\\ 2 x^{2} -8x=0~~~~:~~~~2\\ x^{2} -4x\\ x(x-4)=0\\\\ x'=0~~~~~~~~~~~~~~~~x-4=0\\ ~~~~~~~~~~~~~~~~~~~~~~~~~x''=4\\\\ \boxed{S\{0,4\}}$


Espero ter ajudado e tenha ótimos estudos =))