Explanation:
It's a quadratic equation which simplifies to x²+2x-8
Now if you want to "solve" it then you must be a little more particular with your question because you can do many things with a quadratic equation, you can:
1. Factorise it
2. find the zeros
3. graph it
4. describe the nature of its roots,etc
but let me help you factorise it
x²+2x-8
x²+4x-2x-8
x(x+4)-2(x+4)
(x-2)(x+4)