Solve: `x-3=3x+7`.

Options

A. 5
B. -5
C. 1
D. `10/4`

Answer

To solve the equation \( x - 3 = 3x + 7 \), we will follow these steps:

### Step 1: Rearrange the equation
We want to get all the terms involving \( x \) on one side and the constant terms on the other side. We can start by subtracting \( 3x \) from both sides of the equation.

\[ x - 3 - 3x = 3x + 7 - 3x \]

This simplifies to:

\[ x - 3x - 3 = 7 \]

### Step 2: Combine like terms
Now, combine the \( x \) terms on the left side:

\[ -2x - 3 = 7 \]

### Step 3: Isolate the variable
Next, we need to isolate the term with \( x \). We can do this by adding \( 3 \) to both sides of the equation:

\[ -2x - 3 + 3 = 7 + 3 \]

This simplifies to:

\[ -2x = 10 \]

### Step 4: Solve for \( x \)
Now, we divide both sides by \( -2 \) to solve for \( x \):

\[ x = \frac{10}{-2} \]

This simplifies to:

\[ x = -5 \]

### Final Answer
Thus, the solution to the equation \( x - 3 = 3x + 7 \) is:

\[ x = -5 \]

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