1. x^2-4x+4=(x-2)^2
2. 9x^2+1=6x. 9x^2-6x+1=0. (3x-1)^2=0
3. -(0,04x^2-9m^2)=-(0,2x+3m)*(0,2x-3m)
4. (a+4)*(a-4)
1. x^2-4x+4=(x-2)^2
2. 9x^2+1=6x. 9x^2-6x+1=0. (3x-1)^2=0
3. -(0,04x^2-9m^2)=-(0,2x+3m)*(0,2x-3m)
4. (a+4)*(a-4)