A surveyor takes the measurements shown to find the distance, d, across a river. What is the distance across the river?

No a triangle cannot be formed because when you add the two smallest number together (which would be 11) the have to be bigger than the number it is "against" ( which would be 12)

You're doing something i dont know how to do but search up on google slope calculator maybe that will get you there

“exterior angles of triangles. an exterior (or external) angle is the angle between one side of a triangle and the extension of an adjacent side. try this drag the orange dots on any vertex to reshape the triangle.” look to get to the answer i explained what it means and other things i hope it you .