How do you solve the system of equations $3x - y = 71$ and $4y = x$ ?

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Answer 1 · 2017-01-27T19:06:53

See the entire solution process below:

Step 1) Because the second equation is already solved for $x$ we can substitute $4y$ for $x$ in the first equation and solve for $y$ :

$3(4y) - y = 71$

$12y - y = 71$

$11y = 71$

$(11y)/color(red)(11) = 71/color(red)(11)$

$y = 71/11$

Step 2) Substitute $71/11$ for $y$ in the second equation and calculate $x$ :

$4 xx 71/11 = x$

$284/11 = x$

The solution is $x = 284/11$ and $y = 71/11$

How do you solve the system of equations 3x - y = 713x - y = 71 and 4y = x4y = x?