Answer:
[tex] {(x - 6)}^{2} [/tex]
Step-by-step explanation:
[tex] = {x}^{2} - 12x + 36 \\ = {x}^{2} - (6 + 6)x + 36 \\ = {x }^{2} - 6x - 6x + 36 \\ = x(x - 6) - 6(x - 6) \\ =(x - 6)(x - 6) \\ = {(x - 6)}^{2} [/tex]