I'm about to take an important test in school, and today we did a practise run. There was one question I really didn't know how to work out. It was about the perpendicular height of a triangle, and we were given the base length and the area. Everyone around me knew the answer but I didn't even know where to start! So can anyone tell me how to work out the perpendicular height when given the base length and area and vice versa?