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

$5m+7n-15$
$\bf{\text{Solution Outline:}}$ Use the Distributive Property to simplify the given expression, $2m+n-3(5-m-2n) .$ Then combine like terms. $\bf{\text{Solution Details:}}$ Using the Distributive Property which is given by $a(b+c)=ab+ac,$ the expression above is equivalent to \begin{array}{l}\require{cancel} 2m+n-3(5-m-2n) \\\\= 2m+n-3(5)-3(-m)-3(-2n) \\\\= 2m+n-15+3m+6n .\end{array} By combining like terms, the expression above is equivalent to \begin{array}{l}\require{cancel} 2m+n-15+3m+6n \\\\= (2m+3m)+(n+6n)-15 \\\\= 5m+7n-15 .\end{array}