Complete the square to rewrite the equation in the form: (x – h)2 = p
X2 + 12x - 23 = 0

12/20 can be simplified by factoring out the ones exg
4/8=1/2 because 4/8=1/2 times 4/4 and 4/4=1

so find factors of 12 and 20
12=2 times 2 times 3
20=2 times 2 times 5
there is 2 times 2 that is common to both so
(note: 2*2 means 2 itmes 2)
12/20=(2*2)/(2*2) times 3/5=1 times 3/5=3/5
the simplest form is 3/5 is your answer