10. [tex]10x^2-4 [/tex]
12. [tex]8m+4n+2[/tex]
Explanation
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10.
Distribute
[tex]=6x^2+(4)(x^2)+(4)(-1)[/tex]
[tex]=6x^2+4x^2+-4[/tex]
Combine like terms
[tex]=6x^2+4x^2+-4[/tex]
[tex]=(6x^2+4x^2)+(-4)[/tex]
[tex]=10x^2+-4 [/tex]
12.
Combine like terms
[tex]=8m+14+-12+4n[/tex]
[tex]=(8m)+(4n)+(14+-12)[/tex]
[tex]=8m+4n+2[/tex]
Hope this helps :)
