Which terms are considered like terms in the expression: 25x² + 6y³ + 4x - 25y + 3x² - 4y²?

In the expression 25x² + 6y³ + 4x - 25y + 3x² - 4y², like terms are those that contain the same variable raised to the same power.

In this case, 25x² and 3x² both contain the variable x raised to the power of 2, making them like terms. This allows them to be combined in operations such as addition or subtraction.

The other terms in the expression involve different variables or different powers of the same variable, which is why they do not qualify as like terms with 25x² and 3x². Understanding the concept of like terms is essential in simplifying algebraic expressions and performing operations on them.