Answer:
143
Explanation:
You want the value of the term with degree 0 in the polynomial 12x²-42x+143.
Degrees
The degree of each term is the exponent of the variable. A term with no variables has degree 0.
The term with no variables is also called the constant term. The constant in this polynomial is 143.
The value of the term with degree 0 is 143.
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Additional comment
If there is more than one variable, the degree of the term is the sum of their exponents.