A line passes through the point $(1,-8)$ and has a slope of -9 . Write an equation in slope-intercept form for this line.

Step 1 ：The slope-intercept form of a line is given by \(y = mx + c\), where \(m\) is the slope and \(c\) is the y-intercept.

Step 2 ：We know the slope \(m\) is -9, and we know that the line passes through the point \((1,-8)\). We can substitute these values into the equation to find the y-intercept \(c\).

Step 3 ：Substituting the values we get: \(-8 = -9*1 + c\)

Step 4 ：Solving for \(c\) we get \(c = 1\)

Step 5 ：Now that we have the y-intercept, we can write the equation of the line in slope-intercept form.

Step 6 ：The equation of the line in slope-intercept form is \(\boxed{y = -9x + 1}\)