Solve : `18=1-3a`

Answer

To solve the equation \( 18 = 1 - 3a \), we will follow these steps:

### Step 1: Rearrange the equation
We start with the equation:
\[ 18 = 1 - 3a \]
To isolate the term with \( a \), we can subtract 1 from both sides:
\[ 18 - 1 = -3a \]

### Step 2: Simplify the left side
Now, we simplify the left side:
\[ 17 = -3a \]

### Step 3: Solve for \( a \)
Next, we need to isolate \( a \). To do this, we divide both sides by -3:
\[ a = \frac{17}{-3} \]
This simplifies to:
\[ a = -\frac{17}{3} \]

### Final Answer
Thus, the solution to the equation \( 18 = 1 - 3a \) is:
\[ a = -\frac{17}{3} \]

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