It variates depending on the significant of x
The final solution is all the values that make <span><span><span><span><span>(<span>x+4</span>)</span><span>(<span>x<span>−4</span></span>)</span></span><span>(<span><span>x2</span>+4</span>)</span></span>=0</span><span><span><span><span>x+4</span><span>x<span>-4</span></span></span><span><span>x2</span>+4</span></span>=0</span></span> true.<span>x=<span>−4</span>,4,<span>2i</span>,<span><span>−2</span><span>i</span></span></span>