Question 107303
{{{2x^2-6x+7+7x^3-2x^2+4-3x}}}   Start with the given expression


{{{(2x^2-2x^2)+(-6x-3x)+(7x^3)+(7+4)}}} Group like terms


{{{-9x+7x^3+11}}} Combine like terms



So you are correct
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{{{(5x^4+2x^3-4)-(2x^3+4x-7)}}}   Start with the given expression



{{{5x^4+2x^3-4-2x^3-4x+7)}}}   Distribute the negative



{{{(5x^4)+(2x^3-2x^3)+(-4x)+(-4+7)}}} Group like terms


{{{5x^4-4x+3}}} Combine like terms



So you are correct


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{{{(x-2)(2x^2+x-7)}}} Start with the given expression 



{{{2x^3+x^2-7x-4x^2-2x+14}}} Distribute



{{{(2x^3)+(1x^2-4x^2)+(-7x-2x)+(14)}}} Group like terms


{{{2x^3-3x^2-9x+14}}} Combine like terms



So you are correct


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{{{(12a^4+3a^2)/3a^2}}}  Start with the given expression



{{{12a^4/3a^2+3a^2/3a^2}}}  Break up the fraction



{{{4a^2+1}}}  Divide


Yes there would be a +1 on the end since there is a '+' in the expression and {{{3a^2/3a^2}}} reduces to 1