SOLUTION: [ the perimeter of a rectangle is 120 feet. if the length is four times the width, what are the dimensions of the rectangle? ]

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Question 825452: [ the perimeter of a rectangle is 120 feet. if the length is four times the width, what are the dimensions of the rectangle? ]
Answer by TimothyLamb(4379) About Me  (Show Source):
You can put this solution on YOUR website!
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x = length
y = width
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2x + 2y = 120
x = 4y
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put the system of linear equations into standard form
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2x + 2y = 120
x - 4y = 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 = length = 48 ft
y = width = 12 ft
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system matrix
2 2
1 -4
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inverse of system matrix
0.4 0.2
0.1 -0.2
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determinant of system matrix = -10
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Solve and graph linear equations:
https://sooeet.com/math/linear-equation-solver.php
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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