[tex]a)\\\\5x^2-3x9x^2+4x+5=5x^2-27x^3+4x+5=-27x^3+5x^2+4x+5\\\\b)\\\\-7a-(4a-3a^2)+5a^2-2a^3=-7a-4a+3a^2+5a^2-2a^3=-2a^3+8a^2-11a\\\\c)\\\\-4(2x+0.5)=-8x-2\\\\d)\\\\3(x^2-2)-(5-6x^2)=3x^2-6-5+6x^2=9x^2-11\\\\e) \\\\(x+1)(x+4)=x^2+4x+x+4=x^2+5x+4\\\\f)\\\\-2(2x+3)(2x-1)=-2(4x^2-2x+6x-3)=-2(4x^2+4x-3)=-8x^2-8x+6\\\\g) \\\\(x+7)^2=x^2+14x+49[/tex]