To find the equation of a line in slope-intercept form, we use the formula:
\[ y = mx + b \]
where:
- \( m \) is the slope of the line,
- \( b \) is the y-intercept.
We are given the slope \( m = 8 \) and a point on the line \( (1, 3) \). We can use this point to find the y-intercept \( b \).
- Substitute the slope and the coordinates of the point into the equation:
\[ y = 8x + b \]
- Substitute \( x = 1 \) and \( y = 3 \) into the equation:
\[ 3 = 8(1) + b \]
- Simplify and solve for \( b \):
\[ 3 = 8 + b \]
\[ b = 3 - 8 \]
\[ b = -5 \]
Now that we have both \( m \) and \( b \), the equation of the line in slope-intercept form is:
\[ y = 8x - 5 \]
Thus, the equation of the line is:
\(\boxed{y = 8x - 5}\)