Question

4. Resolva as equações do 2º grau: (40pts)
a) X2- 7x + 10 = 0
b) X2 -X- 12 = 0

Me ajudem ​

Answer 1

$a) \frac{ - 7 \frac{ + }{ - } \sqrt{( - 7 {)}^{2} - 4 \times 1 \times 10} }{2 \times 1} \\ \frac{ - 7 \frac{ + }{ - } \sqrt{9} }{2} \\ {x}^{1} = \frac{ - 7 + 3}{2} = \frac{ - 4}{2} = - 2 \\ {x}^{2} = \frac{ - 7 - 3}{2} = \frac{ - 10}{2} = - 5$

$b) \frac{ - 1 \frac{ + }{ - } \sqrt{( - 1 {)}^{2} } - 4 \times 1 \times ( - 12)}{2 \times 1} \\ \frac{ - 1 \frac{ + }{ - } \sqrt{49} }{2} \\ {x}^{1} = \frac{ - 1 + 7}{2} = \frac{6}{2} = 3 \\ {x}^{2} = \frac{ - 1 - 7}{2} = \frac{ - 8}{2} = - 4$