Someone solve this for me . i missed school, and my teacher won't me.

(2x^2 -2x^4)-(x^4 -x^2)
2x^2 -2x^4 -x^4 +x^2
3x^2 -3x^4

Hope this helps :)

You must distribute the negative sign to the furthermost right set of parentheses. because you have to assume that there is a one between the - and the (. when you do that you get (2x^2-2x^4)+(- x^4-(-)x^2) then combine like terms. 3x^2-3x^4 is the final answer