Question 695616
Hello, 
Let's have N represent nickles and Q be quarters so we can set up 2 equations:
N + Q = 60 or can be written as: N= 60-Q
.05N +.25Q = 5.80
With me so far?
Let's get rid of the decimals by multiplying by 100:
5N + 25Q = 580
Now, let's use substitution:
5(60-Q)+25Q=580
Expand:
300-5Q+25Q=580
Subtract 300:
20Q=280
Divide by 20:
Q=14
So we know that there are 14 quarters and 46 nickles. 
Make sense?
RJ
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