Chapter 1 - Some Basic Concepts of Arithmetic and Algebra - 1.5 - Use of Properties - Problem Set 1.5 - Page 34: 79

$-65$

Combining like terms, the given expression, $ -3x+7x+4x-2x-x ,$ simplifies to \begin{array}{l}\require{cancel} 4x+4x-2x-x \\\\= 8x-2x-x \\\\= 6x-x \\\\= 5x .\end{array} Substituting $ x=-13 ,$ the resulting expression above evaluates to \begin{array}{l}\require{cancel} 5(-13) \\\\= -65 .\end{array}