Write the slope-intercept equation of the function \( f \) whose graph satisfies the given conditions. The graph of \( f \) passes through \( (8,-9) \) and is perpendicular to the line whose equation is \( x=12 \) The equation of the function is \( \square . . . \).

To start, since the line whose equation is \( x=12 \) is a vertical line, any line perpendicular to it must be horizontal. Thus, the slope of the function \( f \) will be \( 0 \). Now, we know that a horizontal line passing through the point \( (8, -9) \) has a constant \( y \)-value of \(-9\). Therefore, the slope-intercept equation will simply be \( f(x) = -9 \). The equation of the function is \( f(x) = -9 \).