How do you solve for the x if $8x=y$ and $2x+y=5$ ?

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Answer 1 · 2018-05-23T23:41:35

Substitute out $y$ in the second equation and solve for $x$ , which is $x=0.5$

The first expression gives us a solution for $y$ in terms of $x$ :

$color(blue)(8x=y)$

We can take this solution and substitute all values of $y$ in equation 2:

$2x+color(blue)y=5$

$2x+color(blue)(8x)=5$

Because we know $color(blue)(y=8x)$ we can make this substitution. Now all that's left is to solve for $x$

$10x=5$

$(cancel(10)x)/color(red)(cancel(10))=5/color(red)(10)$

$color(green)(x=1/2=0.5)$

How do you solve for the x if 8x=y8x=y and 2x+y=52x+y=5?