Question 979441
x+y=12,
5*x+10*y=85
x=12-y
5*(12-y)+10*y=85
60-5y+10*y=85
5*y=25
y=5
x=12-y
x=7 at 5 and  y=5 at 10
check
7+5=12
5*x+10*y=85
5*7+10*5=85
35+50=85
85=85
ok
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