Question 408234
The roots are the values of x where the graph crosses the x axis (y=0)
:
In this equation find the roots using the quadratic formula:
{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}} 
in this equation a=-1; b=812; c=-9600
{{{x = (-812 +- sqrt(812^2-4*-1*-9600 ))/(2*-1) }}}
you should get two solutions
x=800
x= 12