Question 670084

{{{(7y^3+8y^2+1)-(4y^3-8y-9)}}}

first, remove the parenthesis


{{{7y^3+8y^2+1-4y^3+8y+9}}}


now, combine like terms


{{{(7y^3-4y^3)+8y^2+8y+(1+9)}}}


{{{3y^3+8y^2+8y+10}}}