[tex]a)\\\\ -4x-7-3x+7 =-7x\\\\b)\\\\x-2xy+ \frac{1}{2}x- \frac{1}{3}xy =1\frac{1}{2} x-2\frac{1}{3}xy [/tex]
[tex]c)\\\\ -x^2+y^2-2x^2-2y^2= -3x^2-y^2[/tex]
[tex]d)\\\\ -x^2+2x-3x+x^2 =-x[/tex]
[tex]e)\\\\ 4x+4-7x-\frac{1}{2}=3\frac{1}{2}-3x [/tex]
