Combining Like Terms

Like terms have the same variable to the same power. You can combine them by adding or subtracting coefficients.

For example, $3x + 5x = 8x$ because both terms have $x$ to the first power. But $3x + 5x^2$ cannot be combined because the exponents differ.

Similarly, $7n^2 - 2n^2 + 4n = 5n^2 + 4n$. The $n^2$ terms combine, but $n$ stands alone. This simplification makes expressions easier to work with.