Question 83676
X^2=-5X+8
X^2+5X-8=0 
USING THE QUADRATIC EQUATION {{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}} 
WE GET:
X=(-5+-SQRT[5^2-4*1*-8])/2*1
X=(-5+-SQRT[25+32])/2
X=(-5+-SQRT57)/2
X=(-5+-7.55)/2
X=(-5+7.55)/2
X=2.55/2
X=1.275 ANSWER.
X=(-5-7.55)/2
X=-12.55/2
X=-6.275 ANSWER.