Final answer:
The degree of the polynomial − 6ry^2 +5r^4 − 7z is 4, as the term with the highest exponent is 5r^4, where the exponent on r is 4.
Step-by-step explanation:
The degree of a polynomial is the highest exponent of the variable in any term of the polynomial. In the given polynomial − 6ry2 +5r4 − 7z, the degrees of the individual terms are as follows:
- The term − 6ry2 has a degree of 3 (since r has an exponent of 1 and y has an exponent of 2, and 1+2=3).
- The term 5r4 has a degree of 4 (since r has an exponent of 4).
- The term − 7z has a degree of 1 (since z has an exponent of 1).
The highest degree among these terms is 4, so the degree of the entire polynomial is 4.