The equation mx2 + 12x + 9m = 0 has different roots for different values of m. For what values of m will the equation have one repeated root?

b^2 - 4ac = 0 
12^2 - 4m(9m) = 0 
144 = 36m^2 
m^2 = 4 
m = ± 2
Hope This Helps!
-TyyBenjii