Peter R. answered 10/29/22
Experienced Instructor in Prealgebra, Algebra I and II, SAT/ACT Math.
If use slope-intercept form: y = mx + b (m = slope = rise/run); b is y-intercept.
Point is (3, -9); slope = 1/3
-9 = 3/3 + b → -9 = 1 + b → b = -10
so y = 3/x - 10. Need chg to std form. Mult by 3
3y = x - 30 → x - 3y = 30
Using point-slope form: y2 - y1 = m(x2 - x1)
y - (-9) = 1/3(x - 3) →y + 9 = x/3 -1
Mult by 3 to elim fraction; 3y +27 = x - 3 → x - 3y = 30
Check on Desmos Graphing Calculator website.