Chapter P - Mid-Chapter Check Point - Page 71: 5

$x+45$

We start with the given expression: $7x+3[9-(2x-6)]$ We apply the distributive property on the inner parentheses: $7x+3[9-2x+6]$ We combine like terms within the bracket: $7x+3[15-2x]$ We apply the distributive property on the bracket: $7x+45-6x$ We combine like terms: $x+45$