Question 312236
x^2 - 4x = 1 
x^2-4x-1=0
{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}} 
x=(4+-sqrt[-4^2-4*1*-1])/2*1
x=(4+-sqrt[16+4])/2
x=(4+-sqrt20)/2
x=(4+-4.472)/2
x=(4+4.472)/2
x=8.472)/2
x=4.236 ans.
x=(4-4.472)/2
x=-.472/2
x=-.236 ans.