Thanks to all your help, I've gotten my ultrasonic rangefinders working.

Now I'm trying to derive the math behind using two sensors in parallel to accurately map an object. Using only one sensor would give me a single distance, with no idea of angle. With two of them, at a set distance apart and fancing the same direction, I should be able to figure out the exact distance and angle relative to a point.

How do I go about doing this? I tried using right triangles and pythagorean's theorem but it ended with a trivial solution.

When I try to google triangulation methods, most of the equations involve knowing the angles (relative to each sensor) beforehand. How can I do this with just two distances?

Thanks for any help!