SOLUTION: mckenna has 21 coins worth $2.50. some are nickels, some are dimes, and some are quarters. the number of dimes is five less than twice the number of nickels. how many nickels does

Question 823604: mckenna has 21 coins worth $2.50. some are nickels, some are dimes, and some are quarters. the number of dimes is five less than twice the number of nickels. how many nickels does she have?
Answer by TimothyLamb(4379) (Show Source): You can put this solution on YOUR website!
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x + y + z = 21
5x + 10y + 25z = 250
y = 2x - 5
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put the system of linear equations into standard form
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x + y + z = 21
5x + 10y + 25z = 250
2x - y = 5
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copy and paste the above standard form linear equations in to this solver:
https://sooeet.com/math/system-of-linear-equations-solver.php
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answer:
x= nickels = 7
y= dimes = 9
z= quarters = 5
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Solve systems of linear equations up to 6-equations 6-variables:
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