Multiply :
`2a^(2) - 5a - 4` and `-3a`

Answer

To solve the problem of multiplying the expression \(2a^2 - 5a - 4\) by \(-3a\), we will follow these steps:

### Step 1: Distribute \(-3a\) to each term in the polynomial \(2a^2 - 5a - 4\).

We will multiply \(-3a\) with each term of the polynomial:

1. Multiply \(-3a\) by \(2a^2\):
\[ -3a \cdot 2a^2 = -6a^3 \]

2. Multiply \(-3a\) by \(-5a\):
\[ -3a \cdot (-5a) = 15a^2 \]

3. Multiply \(-3a\) by \(-4\):
\[ -3a \cdot (-4) = 12a \]

### Step 2: Combine the results from the multiplications.

Now, we will combine all the results we obtained from the multiplications:
\[ -6a^3 + 15a^2 + 12a \]

### Final Answer:
The final result of multiplying \(2a^2 - 5a - 4\) by \(-3a\) is:
\[ -6a^3 + 15a^2 + 12a \]

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