What is the first step in which the student made an error

Find an equation of the line perpendicular to the graph of 28x-7y=9 that passes through the point at (4,1)

Solve for n? [tex]z = \frac{3}{4} mn[/tex]

Which best describes a central bank's primary goals? limiting inflation and reducing unemployment reducing unemployment and maintaining cash flow controlling stagflation and reducing unemployment managing credit and ensuring the money supply's liquidity