can anyone show me how to write this out into a equation?

Question

find AB if BC = 4, BD = 5, and AD = 2....as far as i know ive been doing right triangles problems that are c^2= a^2+b^2...

its a right traingle

Answer 1

you want formula,please don't use farmulae as possible.try to understand consept,after that you can eaisly find formulae.
by the way your problem is not clear,you should mention that AB,BD,BC,AD are what?(sides of polygon-(which type of polygon)).