Solve by substitution?

yes
1. 1/3x= -7/15-1/5y
2. 1/3x=67/3+4y
therefore
-7/15-1/5y=67/3+4y
-7/15=67/3+4y+1/5y
-7/15-67/3=4y+1/5y
-342/15=21/5y
y=-114/21
y=5and3/7
for x you calculate yourself