SOLUTION: Diane has $2.24 in pennies and nickels. she has three times as many nickels as pennies. how many pennies and how many nickels does she have?

Question 825615: Diane has $2.24 in pennies and nickels. she has three times as many nickels as pennies. how many pennies and 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 = pennies
y = nickels
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x + 5y = 224
y = 3x
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put the system of linear equations into standard form
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x + 5y = 224
3x - y = 0
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copy and paste the above linear system in standard form into this matrix-method solver:
https://sooeet.com/math/system-of-linear-equations-solver.php
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solution:
x = pennies = 14
y = nickels = 42
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system matrix
1 5
3 -1
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inverse of system matrix
0.0625 0.3125
0.1875 -0.0625
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determinant of system matrix = -16
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Solve and graph linear equations:
https://sooeet.com/math/linear-equation-solver.php
---
Solve quadratic equations, quadratic formula:
https://sooeet.com/math/quadratic-formula-solver.php
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Solve systems of linear equations up to 4-equations 4-variables:
https://sooeet.com/math/system-of-linear-equations-solver.php
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