How do you solve $x = 4 y$ $x=4y$ and $3 x - 2 y = 20$ $3x-2y=20$ using substitution?

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Answer 1 · 2018-03-11T18:06:50

$x = 8$ $x=8$

$y = 2$ $y=2$

$x = 4 y$ $x=4y" "$ (let this be equation 1)

$3 x - 2 y = 20$ $3x-2y=20" "$ (let this be equation 2)

So

$3 x - 2 y = 20$ $3x-2y=20$

$3 (4 y) - 2 y = 20$ $3(4y)-2y=20" "$ (putting the value of $x$ $x$ from equation1 in equation2)

$12 y - 2 y = 20$ $12y-2y=20$

$10 y = 20$ $10y=20$

$y = 2$ $y=2$

Therefore, from equation 1

$x = 4 (2) = 8$ $x = 4(2) = 8$

How do you solve x=4yx=4y and 3x−2y=203x-2y=20 using substitution?