Which fraction expresses –30/54 in lowest terms?
a.-10/27
b.-10/18
c. -15/27
d.-5/9

D. - 

“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 .