Since is on the right side of the equation, switch the sides so it is on the left side of the equation.
Find slope of the equation in terms of using the slope intercept form.
Set the known value of equal to the slope of the equation in terms of .
Rewrite the equation as .
Divide each term by and simplify.
Divide each term in by .
Reduce the expression by cancelling the common factors.
Cancel the common factor.
Divide by to get .