This is for a geometry class?? Sounds more like Algebra 2 or maybe the beginning of a pre-calc/college algebra course. Nonetheless, follow below:
You want the equation of any line that goes through (-4, 2).
Let's make it simple: set up y = mx + b and we can even for your own convenience let m be 1. Thus, y = x + b is appropriate. Lets plug in -4 as our x-coord and 2 as our y-cord. We now have: 2 = -4 + b
In this case, (and there are infinitely many), 2 = -4 + 6, so:
y = x + 6 is an equation that goes through (-4, 2).