Question

I neeed to solve this equation with elimination

Answer 1

The solution to the system of equations be:

• x = 3

• y = 9

Explanation:

Given the system of equations

x + y = 12

-x + 2y = 15

Let us solve the system of equations by elimination

`\begin{bmatrix}x+y=12\\ -x+2y=15\end{bmatrix}`

adding the equations

`-x+2y=15`

`+`

`\underline{x+y=12}`

`3y=27`

solve 3y = 27 for y

`3y=27`

divide both sides by 3

`(3y)/(3)=(27)/(3)`

Simplify

`y=9`

For x+y=12 plug in y = 9

`x+9=12`

Subtract 9 from both sides

`x+9-9=12-9`

Simplify

`x=3`

Therefore, the solution to the system of equations be:

• x = 3

• y = 9