



 
Rita, I am sure there are many ways to solve this problem. What I did was to use what I know about the sum and product of the roots of a quadratic polynomial.
If there is only one root, call it k, then 2k =  b/a and k^{2} = c/a and hence [b/(2a)]^{2} = c/a. Apply this to your quadratic polynomial and see if you cab derive the expression r^{2}(1 + m^{2}) = b^{2}. Harley  


Math Central is supported by the University of Regina and The Pacific Institute for the Mathematical Sciences. 