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

Question

3183 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2018-03-11T18:06:50

$x=8$

$y=2$

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

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

So

$3x-2y=20$

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

$12y-2y=20$

$10y=20$

$y=2$

Therefore, from equation 1

$x = 4(2) = 8$

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