Write the slope-intercept equation of the function \( f \) whose graph satisfies the given conditions. The graph of \( f \) passes through \( (-1,8) \) and is perpendicular to the line whose equation is \( x=-15 \). The equation of the function is

To find the slope-intercept equation of the function \( f \), we need to determine the slope first. The line \( x = -15 \) is a vertical line, making its slope undefined. A line perpendicular to a vertical line must be horizontal, meaning its slope is 0. Therefore, the equation of \( f \) will take the form \( y = b \) where \( b \) is the \( y \)-intercept. Since the graph passes through the point \( (-1, 8) \), we know that when \( x = -1 \), \( y = 8 \). Thus, the horizontal line that represents our function is \( y = 8 \). So the equation of the function is: \[ f(x) = 8 \]