Answer:
x=13, y=7. (13, 7).
Step-by-step explanation:
3x+5y=74
x+y=20
-------------
x=20-y
3(20-y)+5y=74
60-3y+5y=74
60+2y=74
2y=74-60
2y=14
y=14/2
y=7
x+7=20
x=20-7
x=13