Chapter 1 - Introduction to Algebraic Expressions - 1.8 Exponential Notation and Order of Operations - 1.8 Exercise Set - Page 67: 101

$-9x+6$

Since the grouping symbol is preceded by a negative sign, then the sign of each term inside the grouping symbol alters once the grouping symbol is removed. Hence, the given expression, $ 2x-7x-(4x-6) $, is equivalent to \begin{array}{l}\require{cancel} 2x-7x-4x+6 .\end{array} By combining like terms, then this simplifies to \begin{array}{l}\require{cancel} -9x+6 .\end{array}