Answer: (3t-2)^2
Step-by-step explanation:
Well, multiply 9 and 4 together to get 36.
Now what factors of 36 add to 12? Well, 6 and 6, so let's rewrite this:
9t^2-6t-6t+4
Now group factor what you can:
3t(3t-2)-2(3t-2)
Now 3t and -2 both share the common factor of (3t-2) so you can rewrite it as:
(3t-2)(3t-2) which is:
(3t-2)^2.
Hope that makes sense or helps!