Chapter 1 - Some Basic Concepts of Arithmetic and Algebra - 1.5 - Use of Properties - Problem Set 1.5 - Page 34: 57

$5a+29$

Using the Distributive Property and then combining like terms, the given expression, $ 3(a-1)-2(a-6)+4(a+5) ,$ simplifies to \begin{array}{l}\require{cancel} 3a-3-2a+12+4a+20 \\\\= (3a-2a+4a)+(-3+12+20) \\\\= 5a+29 .\end{array}