Swap nodes to align 3 or more like terms and simplify them!
The variable part (e.g., x, y, x²). Like terms must share the exact same pronumeral and power.
The number in front (e.g., -4 in -4x). Coefficients don't matter when matching — only the variable matters!
Numbers with no variable (e.g., 9, -3, i² = -1). Constants always match other constants.
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