If `4x+7=12,` what is the value of `8x+3`?

Options

A. `9`
B. `11`
C. `13`
D. `15`

Answer

To solve the equation \(4x + 7 = 12\) and find the value of \(8x + 3\), we can follow these steps:

### Step 1: Solve for \(x\)
Start with the equation:
\[ 4x + 7 = 12 \]

Subtract 7 from both sides to isolate the term with \(x\):
\[ 4x = 12 - 7 \]
\[ 4x = 5 \]

### Step 2: Divide by 4
Now, divide both sides by 4 to solve for \(x\):
\[ x = \frac{5}{4} \]

### Step 3: Substitute \(x\) into \(8x + 3\)
Now that we have the value of \(x\), we can substitute it into the expression \(8x + 3\):
\[ 8x + 3 = 8\left(\frac{5}{4}\right) + 3 \]

### Step 4: Simplify \(8x\)
Calculate \(8 \times \frac{5}{4}\):
\[ 8 \times \frac{5}{4} = \frac{8 \times 5}{4} = \frac{40}{4} = 10 \]

### Step 5: Add 3
Now add 3 to the result:
\[ 8x + 3 = 10 + 3 = 13 \]

### Final Answer
Thus, the value of \(8x + 3\) is:
\[ \boxed{13} \]

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