Answer:
x² +5x +6
Step-by-step explanation:
First of all, eliminate parentheses. The minus sign on the second term affects all terms inside parentheses:
x² +6x +7 -x -1
Group like terms:
(x²) +(6x -x) +(7 -1)
Simplify those groups:
x² +5x +6 . . . . matches the last selection
