1) [tex]48ab+16 a^{2} = 16a(3b+a)[/tex]
2) [tex] 30m^{2} -45m= 15m(2m-3)[/tex]
3) [tex] x^{2} +5x+6= (x+3)(x+2)[/tex]
4) [tex] y^{2}-4x-21= (y-7)(y+3) [/tex]
5) [tex] m^{2} +4mn+4 n^{2}= (m+2n)^{2} [/tex]
6) [tex]9 z^{2}+3 z^{2}-2= 12 z^{2} -2= 2(6 z^{2}-1) [/tex]
