Chapter 8 - Polynomials and Factoring - 8-5 Factoring X(squared) + bx + c - Practice and Problem-Solving Exercises - Page 504: 42

The factors of $x^{2}$-10x-24 are (x-12)(x+2)

$x^{2}$-10x-24=(x-6)(x-4) What the student did wrong was that the factors are incorrect -6+(-4)=-10 -6$\times$(-4)=+24 Thus multiplying -6$\times$(-4) does not give us -24. Thus the factors are -12 and +2 -12+2=-10 -12$\times$2=-24 $x^{2}$-10x-24=(x-12)(x+2)