Can Anyone Workout This Problem For Me

Hi Can Anyone Help Me Solve This Algebra Problem, If So Please Work It Out For Me. Thank You
(2u^3+6u^2+3)+(2u^3-7u+6)

Just add the like terms

(2u^3+6u^2+3)+(2u^3-7u+6)

=(2u^3+2u^3) +6u^2 -7u +(3+6)

=4u^3 +6u^2 -7u +9

question
(2u^3+6u^2+3)+(2u^3-7u+6)

the answer is
4u^3 + 6u^2 -7u + 9

did you mean,
(2u^3+6u^2+3)+(2u^3-7u+6)=0

if so,4u^3 + 6u^2 -7u + 9 = 0

solving using calculator,
roots are -2.5385
0.51926
0.51926

2+2=4
4u^3+6u^2-7u+9