To solve this equation, we must first expand the left side of the equation:

(х+2)(3х²+7х+1) = 3х³ + 7х² + х + 6х² + 14х + 2

Now, combine like terms:

3х³ + 7х² + х + 6х² + 14х + 2 = 3х³ + 13х² + 15х + 2

Now, set the expanded equation equal to the right side of the equation:

3х³ + 13х² + 15х + 2 = х² - 4

Now, combine like terms and set the equation equal to 0:

3х³ + 13х² + 15х + 2 - х² + 4 = 0
3х³ + 12х² + 15х + 6 = 0

Unfortunately, this equation cannot be simplified further. The solution to this equation will involve using the cubic formula or another method to find the roots of the equation.