Chapter 4 Quadratic Functions and Factoring - 4.3 Solve x(squared) + bx + c = 0 - 4.3 Exercises - Skill Practice - Page 256: 17

$(x-12)^2$

Since the coefficient of the squared term is one, we know that the expression must factor to: $$ (x\pm a)(x\pm b)$$ Here, we see that a and b must multiply to get $144$ and add to get $-24$. Thus, we find that the solution is: $$(x-12)(x-12)=(x-12)^2$$