Question 43661
{{{rm = t^2 - mt}}}
or {{{t^2 - mt - rm = 0}}}
This is a quadratic equation in 't'.
Comparing with standard quadratic equation: {{{ax^2 + bx + c = 0}}}
a = 1, b = -m, c = -rm
Use the quadratic formula {{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}}.
Here, 'x' is replaced by 't'.
So, {{{t = (-(-m) +- sqrt( (-m)^2-4*1*(-rm) ))/(2*1) }}}
or {{{t = (m +- sqrt( m^2 + 4rm))/2 }}}