Question 300876
{{{(x-10)(x-4)-5=0}}}
Graphically it looks like {{{x=5}}} and {{{x=9}}} are solutions.
Plug them into the equation to verify. 
{{{ graph( 300, 300, -5, 10, -5, 5, (x-10)(x-4)+5) }}} 
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{{{x^2-4x-1=0}}}
{{{ graph( 300, 300, -2, 5, -5, 5, x^2-4x-1) }}} 
Won't work graphically.
Use the quadratic formula.
{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}} 
{{{x = (4 +- sqrt( 16-4*1*(-1)))/(2*1) }}}
{{{x = (4 +- sqrt( 20 ))/2 }}}  
{{{x = (4 +- 2sqrt( 5 ))/2 }}}
{{{x = 2 +- sqrt( 5 ) }}}