Final answer:
The given polynomial is a quartic trinomial. The leading coefficient is 5. An example of a quadratic trinomial with a leading coefficient of -9 and a constant term of 15 is -9x² + 6x + 15.
Step-by-step explanation:
The given polynomial is 5x4 – 6x³ + 12x² – 5a.
Name the polynomial by degree and the number of terms:
A polynomial is named by its highest degree and the number of terms it contains. This polynomial's highest degree term is x4, which makes it a quartic polynomial. Since there are four terms in the expression, it is also called a quartic trinomial.
Find the leading coefficient:
The leading coefficient is the coefficient of the term with the highest power of x. Here, the leading coefficient is 5
Write a quadratic trinomial:
A quadratic trinomial with a leading coefficient of -9 and a constant term of 15 could be written as -9x² + bx + 15, where b is any real number. An example could be -9x² + 6x + 15.