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Solve this x²+8/10 -x = 10/2

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x^2+(8)/(10)-x=(10)/(2)\\ x^2-x+(8)/(10)-(10)/(2)=0\\ x^2-x+(8)/(10)-(50)/(10)=0\\ x^2-x-(42)/(10)=0\\ x^2-x+(1)/(4)-(1)/(4)-(42)/(10)=0\\ (x-(1)/(2))^2=(1)/(4)+(42)/(10)\\ (x-(1)/(2))^2=(5)/(20)+(84)/(20)\\ (x-(1)/(2))^2=(89)/(20)\\ x-(1)/(2)=\sqrt{(89)/(20)} \vee x-(1)/(2)=-\sqrt{(89)/(20)}\\ x=(1)/(2)+(√(89))/(√(20)) \vee x=(1)/(2)-(√(89))/(√(20))\\

x=(1)/(2)+(√(89))/(2√(5)) \vee x=(1)/(2)-(√(89))/(2\sqrt5)}\\ x=(1)/(2)+(√(445))/(10) \vee x=(1)/(2)-(√(445))/(10)}\\ x=(5+√(445))/(10) \vee x=(5-√(445))/(10)}\\
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