if we take the black boxes as representation of negative numbers, and the white boxes as a representation of positive numbers, then we get:
[tex]-x^2+x-x-x+1+1+1+1-1+x^2-1-1+x+x[/tex]
after combining the similar terms we get:
[tex](-x^2+x^2)+(x-x-x+x+x)+(1+1+1+1-1-1-1)=x+1[/tex]
therefore, the final expression is x + 1
