Chapter 4 - Polynomials - 4.7 Polynomials in Several Variables - 4.7 Exercise Set - Page 284: 44

$-5b$

The given sentence translates to the expression, $ [(2a+b)+(3a-4b)]-(5a+2b) .$ Removing the grouping symbols and then combining like terms, then the expression above simplifies to \begin{array}{l}\require{cancel} 2a+b+3a-4b-5a-2b \\\\= (2a+3a-5a)+(b-4b-2b) \\\\= 0a-5b \\\\= -5b .\end{array}