Originally Posted by

**jhonwashington** Hello Soroban, I'm having a test about this stuff in a few days, so I thought it would be better to ask you my questions on this thread rather than starting a new thread.

My problem starts right after factoring by grouping.

I understand until this part

x^2**(x+2)-(x+2)=**0

but then I'm totally lost in the next part when you say

"and we have **(x+2)(**x^2-1)"

I don't understand, when factoring by group you have two times (x+2) but then you only put it only once, I put in bold the part which confuses me, also where did you get from that

(x^2-1)?

Thank you so much for your help Soroban.