It is easier to do this in point-slope form first, then convert to slope-intercept later on.
Point slope equation is (y-y)=m(x-x), where m is the slope, and the second variables of the parenthesis is the point.
Now we just input the numbers in.
y+8=3(x-8)
The 8 is positive for the y because it is backwards for these types of equations.
And then we can distribute the other side.
y+8=3x-24
Then we subtract 8 from the y to isolate the y. Add the negatives.
y=3x-32
Hope I helped!