We are given the line equation \( Ax + By + C = 0 \), which passes through the point \( (-10, 7) \) and is perpendicular to the line \( 11x - 8y - 16 = 0 \).
1. Step 1: Find the slope of the given line
The slope of the line \( 11x - 8y - 16 = 0 \) can be found by rewriting the equation in slope-intercept form \( y = mx + b \), where \( m \) is the slope:
\[
11x - 8y - 16 = 0 \quad \Rightarrow \quad -8y = -11x + 16 \quad \Rightarrow \quad y = \frac{11}{8}x - 2
\]
Thus, the slope of this line is \( m_1 = \frac{11}{8} \).
2. Step 2: Find the slope of the perpendicular line
The slope of the line perpendicular to this one is the negative reciprocal of \( \frac{11}{8} \), which is:
\[
m_2 = -\frac{8}{11}
\]
3. Step 3: Use the point-slope form of the line equation
The line passes through the point \( (-10, 7) \), so we use the point-slope form to write the equation of the line:
\[
y - 7 = -\frac{8}{11}(x + 10)
\]
Simplifying this equation:
\[
y - 7 = -\frac{8}{11}x - \frac{80}{11}
\]
\[
y = -\frac{8}{11}x + \frac{7}{11} - \frac{80}{11} = -\frac{8}{11}x - \frac{73}{11}
\]
4. Step 4: Convert the equation to standard form
Multiply through by 11 to eliminate the denominator:
\[
11y = -8x - 73
\]
Rearranging into the standard form \( Ax + By + C = 0 \):
\[
8x + 11y + 73 = 0
\]
Thus, \( A = 8 \), \( B = 11 \), and \( C = -26 \).