degree of algebraic terms
In SCHAUM’S Easy OUTLINES PRECALCULUS book example 1.7(e) it says x3y2-30x4 has a degree of 5.
The degree of a term in a polynomial is the exponent of the variable, or,
if more than one variable is present, the sum of the exponents of the variables.
The degree of a polynomial with more than one term is the largest of
the degrees of the individual terms.
So my question is, if x4 is larger than x3, why isn't x4 used with y2 to make a degree of 6 instead of 5