Factor the polynomial y^2 +24y +144

+24y+144
Firstly, search for a GCF. , 24y, and 144 have no common GCF.
Look at the polynomial. You need to find two numbers that, when multiplied together, their answer adds to give you 24 and multiplies to give you 144. The number is 12.
So now, you set up the factored polynomial like this:
(y+12)(y+12)
While not necessary, it is always a good idea to check:
y·y= 
12·y=12y
12·y=12y
12·12=144
Now set it up like this:
+12y+12y+144
Combine like terms. 12y and 12y are like terms.
Now, the polynomial reads +24y+144.
Our answer, (y+12)(y+12), is correct.
Hope this helps! (I did a lesson on this last night for homework so its fresh in my mind :D)

It is going to be the third choice