Answer :

The simplified expression to a polynomial is = 3x³ + 14x² -22x +21

What is a polynomial?

A polynomial is the mathematical expression that contains variables which are related to each other through addition, subtraction, multiplication and division.

The expression (x−3)(3x² +5x−7) can be simplified below;

X * 3x² = 3x³

X *5x = 5x²

X * -7 = -7x

-3 * 3x² = -9x²

-3 * 5x = -15x

-3 * -7 = 21

When the whole values are arranged the following is gotten,

3x³ + 5x² -9x²-15x-7x +21

3x³ + 14x² -22x +21

Therefore, the simplified expression to the polynomial is = 3x³ + 14x² -22x +21

Learn more about polynomials here:

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