If `16,000=400(x+9)`, what is the value of x?

Options

A. `391`
B. `310`
C. `40`
D. `31`

Answer

To solve the equation \( 16000 = 400(x + 9) \), we can follow these steps:

### Step 1: Divide both sides by 400
To isolate the term containing \( x \), we first divide both sides of the equation by 400.

\[ \frac{16000}{400} = x + 9 \]

### Step 2: Simplify the left side
Now, we simplify the left side:

\[ \frac{16000}{400} = 40 \]

So, we have:

\[ 40 = x + 9 \]

### Step 3: Isolate \( x \)
Next, we need to isolate \( x \) by subtracting 9 from both sides:

\[ 40 - 9 = x \]

### Step 4: Calculate the value of \( x \)
Now, we perform the subtraction:

\[ x = 31 \]

Thus, the value of \( x \) is \( 31 \).

### Final Answer:
\[ x = 31 \]

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