A line equation written in slope-intercept form is
[tex]y=mx+b[/tex]
Where m represents the slope of the line and b the y-intercept. The given line in the text is
[tex]f(x)=-5x-3[/tex]
This line have a slope equal to - 5 and an intercept equal to - 3. Parallel lines have the same slope, therefore, our desired line have the following format
[tex]g(x)=-5x+b[/tex]
To find the intercept, we can use the point that belongs to our line.
[tex]g(2)=12\Rightarrow12=-5\cdot2+b\Rightarrow b=22[/tex]
Then, our line is
[tex]g(x)=-5x+22[/tex]