Classify into monomials, binomials and trinomials.
`3a-5b`

Answer

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

### Step 1: Identify the terms in the expression
The given expression is \(3a - 5b\). We need to identify how many distinct terms it has.

### Step 2: Count the terms
In the expression \(3a - 5b\):
- The first term is \(3a\).
- The second term is \(-5b\).

So, we have a total of **2 terms**.

### Step 3: Classify the expression
Now, we can classify the expression based on the number of terms:
- A **monomial** has only **1 term**.
- A **binomial** has **2 terms**.
- A **trinomial** has **3 terms**.

Since our expression \(3a - 5b\) has **2 terms**, it is classified as a **binomial**.

### Final Answer:
The expression \(3a - 5b\) is a **binomial**.

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