If `18x+42y=66`, what is the value of `3x+7y`?

Answer

To solve the equation \( 18x + 42y = 66 \) and find the value of \( 3x + 7y \), we can follow these steps:

### Step 1: Factor out the common factor
We notice that both terms on the left side of the equation \( 18x + 42y \) have a common factor of 6. We can factor this out.

\[ 18x + 42y = 6(3x + 7y) \]

### Step 2: Rewrite the equation
Now we can rewrite the original equation using the factored form:

\[ 6(3x + 7y) = 66 \]

### Step 3: Isolate \( 3x + 7y \)
To isolate \( 3x + 7y \), we divide both sides of the equation by 6:

\[ 3x + 7y = \frac{66}{6} \]

### Step 4: Simplify the right side
Now we simplify the right side:

\[ 3x + 7y = 11 \]

### Conclusion
Thus, the value of \( 3x + 7y \) is \( 11 \).

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