Substitute teachers with Greenwood School District get paid by the day, although subs with teaching credentials earn a different amount than subs without credentials. Yesterday, 10 non-credentialed subs (x) and 10 credentialed subs (y) taught in the district. That cost the district $1,560. Today, 3 non-credentialed subs and 10 credentialed subs taught, receiving $1,077 from the district.
Choose the correct system of equation.

A.{10x+10y=15603x+10y=1077
B.{20x+13y=1560x+y=1077
C.{10x+3y=107710x+10y=1560