Question

Solve system by using the substitution method.

y=2x+9
8x-3=y


( ? , )

Answer 1

`x = 2; y = 13`

Explanation:

⇒
`4y = 8x + 36` [Multiply equation 1 by 4]

⇒
`3y = 39` [Subtract equation 2 from eq 1]

*Here I do 4y - y = 3y; 8x - 8x = 0; 36 - -3 = 39.

⇒
`y = 13` [Divide both sides by 3]

⇒
`13 = 2x + 9` [Sub in y]

⇒
`2x = 4` [Subtract 9 from both sides]

⇒
`x = 2` [Divide both sides by 2]

Hope this helps! :D