Question

which is an equation for the line with slope 1/3 through (-2,1)

Answer 1

y=(1/3)x+ 5/3

Answer 2

If you aren't looking for any specific type of equation, you could write it in point slope form, which is\[y-a = m(x-b)\]
Where m is your slope.
a is 1 and b is -2 because they relate as -2 = y and 1 = x