Simplify (x+3x^4)+(5x-3x^4)

$(x + 3 x^{4}) + (5 x - 3 x^{4})$

Remove parentheses.

$x + 3 x^{4} + 5 x - 3 x^{4}$

Combine the opposite terms in $x + 3 x^{4} + 5 x - 3 x^{4}$ .

Subtract $3 x^{4}$ from $3 x^{4}$ .

$x + 5 x + 0$

Add $x + 5 x$ and $0$ .

$x + 5 x$

Add $x$ and $5 x$ .

$6 x$