Answer:
s=4, c=7. (4, 7).
Step-by-step explanation:
3s+9c=75
8s+5c=67
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simplify 3s+9c=75 into s+3c=25,
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s+3c=25
8s+5c=67
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s=25-3c
8(25-3c)+5c=67
200-24c+5c=67
200-19c=67
19c=200-67
19c=133
c=133/19
c=7
s+3(7)=25
s+21=25
s=25-21
s=4
