X squared over x+ 2+4x =?

Do you mean

$$\frac{x^2}{x+2}+4x ?$$     If you do this is how you should have presented it.    x^2/(x+2) +4x

 

To make double sure we understand you coule REALLY stress you meaning this way.   [x^2/(x+2)] +4x

 

$$\frac{x^2}{x+2}+4x \\\\
= \frac{x^2}{x+2}+\frac{4x(x+2)}{x+2} \\\\
= \frac{x^2+4x(x+2)}{x+2} \\\\
= \frac{x^2+4x^2+8x}{x+2} \\\\
= \frac{5x^2+8x}{x+2} \\\\
= \frac{5x^2+8x}{x+2} \\\\$$