SOLUTION: kevin is saving money. he only has $20 dollar bills and $5 dollar bills. he has a total of 25 bills and a total of $410 dollars. how many $5 bills does he have? how many $20 bills

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Question 1071032: kevin is saving money. he only has $20 dollar bills and $5 dollar bills. he has a total of 25 bills and a total of $410 dollars. how many $5 bills does he have? how many $20 bills does he have? (using substitution)
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
x, how many $5
y, how many $20

system%28x%2By=25%2C5x%2B20y=410%29

Simplify the money equation first.
x%2B4y=82

Simpler system: system%28x%2By=25%2Cx%2B4y=82%29.
Do the substitution and solving any way you want. Easiest might be x=25-y and then %2825-y%29%2B4y=82.