To find the missing y-value, we can use the formula for the slope of a line given two points \((x_1, y_1)\) and \((x_2, y_2)\):
\[ \text{slope} = \frac{y_2 - y_1}{x_2 - x_1} \]
From the table, we have two points:
- \( (1, 3) \) (where \(x_1 = 1\) and \(y_1 = 3\))
- \( (2, y_2) \) (where \(x_2 = 2\) and \(y_2\) is the missing value)
Given that the slope is \(4\), we can set up the equation:
\[ 4 = \frac{y_2 - 3}{2 - 1} \]
This simplifies to:
\[ 4 = y_2 - 3 \]
Now, solve for \(y_2\):
\[ y_2 = 4 + 3 \] \[ y_2 = 7 \]
Thus, the missing \(y\)-value is \(7\).
So, the answer is 7.