You may want to review solving linear equations first.
The intercepts of a line are where it crosses the x- and y-axes. Lines usually have two intercepts, the x-intercept and the y-intercept. You find the x-intercept by substituting 0 into the equation wherever you see a y. Now you have an equation that you can solve for x. To find the y-intercept, it's the other way around; you put 0 in for x and then solve for y.
For example, suppose you had to find the intercepts of the equation 2x + 3y = 6. To find the x-intercept, you put 0 in for y, which makes the equation 2x = 6. The solution of this is x = 3, so 3 is the x-intercept; this means the line goes through the point (3, 0). To find the y-intercept, you put in 0 for x, which makes the equation 3y = 6. Now the solution is y = 2, so 2 is the y-intercept; this means the line goes through (0, 2).
Note that intercepts are always numbers; they can't have letters in them. Also, if one of the equations is an identity or a contradiction, then that intercept doesn't really make sense. On this website, you should indicate that by leaving it blank. (You still need to compute the other intercept, though!)