Aha! I love these types of questions. This is where you are going to use point-slope form!
As a reminder...point slope form is
![y - y^1 = m(x-x^1)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/hrrtrhej08uaeu4wz9ogoy37aq1ft89iky.png)
So if we have our coordinates (4, -7) -- 4 would be
![x^1](https://img.qammunity.org/2019/formulas/mathematics/middle-school/1ljcc8jbfzbh4e62sw00jpcjm1ek7jyu3g.png)
and -7 would be
![y^1](https://img.qammunity.org/2019/formulas/mathematics/middle-school/pgkcph1mgfkkamtvhu7hcjlzkxnvob3hxv.png)
-- now you need to plug them in.
But remember m = slope.
y + 7 = 3 (x - 4) -- now convert into standard form.
Standard form: y = 3x - 19