# Is the expression 2y-5+3y^2 a polynomial?

Aug 22, 2017

It's a trinomial.

#### Explanation:

It can be expressed as $3 {y}^{2} + 2 {y}^{1} - 5 {y}^{0}$ which has 3 terms. polynomials are expressions with more than 3 terms when written in descending powers.
Example: ${x}^{5} + 2 {x}^{4} - 0 {x}^{3} + 0 {x}^{2} + 0 {x}^{1} + 0 {x}^{0}$ would not be a binomial, because it has more than two terms when written in descending powers and using zero coefficients.