Classify into monomials, binomials and trinomials:
3x - 5y.

Answer

To classify the expression \(3x - 5y\) into monomials, binomials, and trinomials, we can follow these steps:

### Step 1: Understand the Definitions
- **Monomial**: An algebraic expression that consists of only one term.
- **Binomial**: An algebraic expression that consists of exactly two terms.
- **Trinomial**: An algebraic expression that consists of exactly three terms.

### Step 2: Identify the Terms in the Expression
The given expression is \(3x - 5y\). We need to identify how many distinct terms it contains.

### Step 3: Count the Terms
In the expression \(3x - 5y\):
- The first term is \(3x\).
- The second term is \(-5y\).

### Step 4: Determine the Number of Terms
We can see that there are two distinct terms in the expression: \(3x\) and \(-5y\).

### Step 5: Classify the Expression
Since there are exactly two terms in the expression \(3x - 5y\), we classify it as a **binomial**.

### Final Answer
The expression \(3x - 5y\) is classified as a **binomial**.

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