## Elementary and Intermediate Algebra: Concepts & Applications (6th Edition)

$(d-5)(d-2)$
The 2 numbers whose product is $ac= 1(10)=10$ and whose sum is $b= -7$ are $\left\{ -5,-2 \right\}.$ Using these two numbers to decompose the middle term of the given trinomial, $d^2-7d+10 ,$ then the factored form is \begin{array}{l} d^2-5d-2d+10 \\\\= (d^2-5d)-(2d-10) \\\\= d(d-5)-2(d-5) \\\\= (d-5)(d-2) .\end{array}