Hey common_sense_seeker.

The key hint is that both triangles (the whole one and the smaller one down the bottom) are similar which means that they have the same angles if the line with 10ft above it is also at a right angle.

If you know a side and an angle in a right angled triangle, you can get the other side. Using this hint, you should be able to get an expression for x and also for x + y means one minus the other will give you y.

To start off, look at the big triangle and think about how you can get the angle given two sides of a right angled triangle.