Question

Y=–3x + 6y=9 What is the solution to the system of equations? (–21, 9) (9, –21) (–1, 9) (9, –1)

Answer 1

The solution is
`(-1,9)`

Step-by-step explanation

We want to solve the simultaneous equations

`y=-3x+6---(1)`

and

`y=9--(2)`.

We substitute equation (2) in to equation (1), to obtain

`9=-3x+6`

This has now become a linear equation in a single variable
`x`.

We solve for x by grouping like terms.

`9-6=-3x`

`3=-3x`

We divide through by negative 3 to get;

`-1=x`.

Hence, the solution is
`(-1,9)`