Question

How do you solve `6x-9y=-3` and `9x+92=y` using substitution?

Answer 1

`y=-7`
`x=-11`

Explanation:

`6x-9y=-3` --- (1)
`9x+92=y` --- (2)

Sub (2) into (1)
`6x-9y=-3`
`6x-9(9x+92)=-3`
`6x-81x-828=-3`
`75x=-825`
`x=-11` --- (3)

Sub (3) into (2)
`9x+92=y`
`9(-11)+92=y`
`-99+92=y`
`y=-7`