FMO 2026 - Grade 9 - International - Paper 05 Question 5

For numbers $a,b$, define $a\odot b=a^2 b+a$. For example, $3\odot 2=3^2\times 2+3=21$. Given $(x-2)\odot x=x^3+x^2+15 x+3$, find $x$.