Last question, a friend out haha : d

 Ax + By = C

3x + 2y = 12

A=3, B = 2 and C = 12

“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 .