i don't remember how to add and subtract polynomials someone please help explain[tex]( - 2x + 4) + 2(2x + 1[/tex][tex]2(3x + 5) - 4(x - 1)[/tex][tex]2(x - 7) + (8x + 20)[/tex]

i dont remember how to add and subtract polynomials someone please help explaintex 2x 4 22x 1textex23x 5 4x 1textex2x 7 8x 20tex class=