Answer :
Considering that it's highest exponent is of 3, the expression 5x³ + 2x - 3 is a cubic expression.
What is the degree of a polynomial?
The degree of a polynomial is given by the highest exponent.
The highest exponent of the expression 5x³ + 2x - 3 is a 3, hence it is a cubic expression.
More can be learned about the degree of a polynomial at https://brainly.com/question/24380382
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