Quadratic Equations _ If the roots of the Quadratic Equation (1+m2) x2 + 2mcx + (c2-a2)=0 are equal

Quadratic Equations | If the roots of the Quadratic Equation (1+m2) x2 + 2mcx + (c2-a2)=0 are equal show that c2=a2(1+m2).