Can someone me complete this two-column proof?

an explanation on how to do it would be nice.. (picture below)

(and don't answer if you don't know, .)

given: < 2 and < 5 are supplementary.
prove: l || m

Which function is represented by the graph

Afruit stand has to decide what to charge for their produce. they need $10 for 4 apples and 4 oranges. they also need $15 for 6 apples and 6 oranges. we put this information into a system of linear equations. can we find a unique price for an apple and an orange?

Sam claims that cos x =sin y if x and y are congruent angels. is sam correct ?