when finding the intercept of a line with ax + by = c you make the other variable 0. This is due to the fact that if it is x intercept it it (x,0) and if it is y intercept it is (0,y) so if you plug in the other variable is 0.
x intercept : (5,0)
y intercept : (0,-2)
When finding a slop and knowing 2 points you can use the formula.
