Given expression,
[tex](5x^2+2x+1)+(6x^2-3x+9)=(11x^2-x+10)[/tex]
Option B is correct.
[tex](-3x^2+6x-12)+(5x+9)=(-3x^2+11x-3)[/tex]
Option A is correct.
[tex](8x+16)-(3x^2-3x-15)=(-3x^2+11x+31)[/tex]
Option D is correct.
[tex](5x^2+23x-7)-(x^2-4x+21)=(4x^2+27x-28)[/tex]
Option C is correct.
