How do you solve the following system using substitution?: $y = x - 5, y = 2 x$ $y=x-5, y=2x$

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Answer 1 · 2015-10-24T15:48:08

$x = - 5$ $x=-5$
$y = - 10$ $y=-10$

You simply have to substitute $x$ $x$ or $y$ $y$ from the first equation to $x$ $x$ or $y$ $y$ in the second equation.

So in the first equation, the value of $y$ $y$ is $x - 5$ $x-5$ . You just have to substitute this value into $y$ $y$ in the second equation.

$[1] X X y = 2 x$ $[1]color(white)(XX)y=2x$

$[2] X X x - 5 = 2 x$ $[2]color(white)(XX)x-5=2x$

$[3] X X - 5 = 2 x - x$ $[3]color(white)(XX)-5=2x-x$

$[4] X X x = - 5$ $[4]color(white)(XX)color(blue)(x=-5)$

Now that we have the value of $x$ $x$ , we can plug it into either of the two equations to solve for $y$ $y$ .

$[1] X X y = x - 5$ $[1]color(white)(XX)y=x-5$

$[2] X X y = (- 5) - 5$ $[2]color(white)(XX)y=(-5)-5$

$[3] X X y = - 10$ $[3]color(white)(XX)color(red)(y=-10)$

How do you solve the following system using substitution?: y=x−5,y=2xy=x-5, y=2x