document.write( "Question 827008: tina has 20 coins in dimes and quarters. their total value is $3.20. how many coins of each type does she have? \n" ); document.write( "

Algebra.Com's Answer #498385 by TimothyLamb(4379) $\"\"$ $\"About$

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---
\n" ); document.write( "x = dimes
\n" ); document.write( "y = quarters
\n" ); document.write( "---
\n" ); document.write( "x + y = 20
\n" ); document.write( "10x + 25y = 320
\n" ); document.write( "---
\n" ); document.write( "copy and paste the above linear system in standard form into this matrix-method solver:
\n" ); document.write( "https://sooeet.com/math/system-of-linear-equations-solver.php
\n" ); document.write( "---
\n" ); document.write( "solution:
\n" ); document.write( "x = dimes = 12
\n" ); document.write( "y = quarters = 8
\n" ); document.write( "---
\n" ); document.write( "system matrix
\n" ); document.write( "1 1
\n" ); document.write( "10 25
\n" ); document.write( "---
\n" ); document.write( "inverse of system matrix
\n" ); document.write( "1.6666667 -0.066666667
\n" ); document.write( "-0.66666667 0.066666667
\n" ); document.write( "---
\n" ); document.write( "determinant of system matrix = 15
\n" ); document.write( "---
\n" ); document.write( "Solve and graph linear equations:
\n" ); document.write( "https://sooeet.com/math/linear-equation-solver.php
\n" ); document.write( "---
\n" ); document.write( "Solve quadratic equations, quadratic formula:
\n" ); document.write( "https://sooeet.com/math/quadratic-formula-solver.php
\n" ); document.write( "---
\n" ); document.write( "Solve systems of linear equations up to 6-equations 6-variables:
\n" ); document.write( "https://sooeet.com/math/system-of-linear-equations-solver.php \n" ); document.write( "

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