Factoring out a Constant Practice AK

In the following quadratic equations, factor out a constant, if possible:  

1. $8x^2+4x-10=0\rightarrow 2(4x^2+2x-5)=0$
2. $2x^2-6x+9=0 \rightarrow \text{No constant can be factored out}$
3. $4x^2-4x=-20\rightarrow 4(x^2-x+5)=0$
4. $8x^2=4x-8\rightarrow 4(2x^2-x+2)=0$
5. $3x^2+6=-36x\rightarrow 3(x^2+12x+2)=0$
6. $2x^2-6x+6=0\rightarrow 2(x^2-3x+3)=0$
7. $-6x+18=12x^2\rightarrow 6(2x^2+x-3)=0$
8. $5x^2-2x+10=0\rightarrow \text{No constant can be factored out}$
9. $6x^2+6x+6=0\rightarrow 6(x^2+x+1)=0$
10. $3x^2-12x=-12\rightarrow 3(x^2-4x+4)=0$