Question 1169112

a) 

{{{a^2 - 100=a^2-10^2=(a-10)(a+10)}}}


b) 

{{{9b^3 - 12b^2 - 6=3(3b^3 - 4b^2 - 2)}}}


c)

{{{ c^2 + 6c + 8= c^2 + 4c+2c + 8= (c^2 + 4c)+(2c + 8)=c(c + 4)+2(c + 4) =(c + 4) (c + 2)}}}