Step-by-step explanation:
2x^2 - 4x - 8 = 0
x^2 - 2x - 8 =0
[tex]x = 2 ( - )(+) \sqrt{2 {}^{2} + 4.1.4 } \div 2.1 \\ x = 2( + )( - ) \sqrt{4 + 16} \div 2 \\ x = 2( - )( + ) \sqrt{20} \div 2 \\ x = 2( - )( + )2 \sqrt{5} \div 2 \\ x = 2(1( - )( + ) \sqrt{5} \div 2 \\ thefore \: x = 1 + \sqrt{5} \: or \: x = 1 - \sqrt{5} [/tex]
