We need the equation in the format of y=mx+b for which m=slope, and b is the y-intercept, the value of y when x=0.
Let's add 5 to both sides...
Let's subtract 3x from both sides...
Let's divide both sides by 2...
The slope of this line is -3/2.
The slope of the line perpendicular to such is positive 2/3.
The y-intercept, b, is unknown at this time.
Let's plug-in the one coordinate provided to establish such; (2,1).
Let's subtract 4/3 from both sides...