Question

-X + 9y = 363x + 3y = 42How do I solve using the elimination method

Answer 1

Given:

-x + 9y = 36 .......(1)

3x + 3y = 42 ........(2)

The equations can be solved using elimination method.

Multiply equation (2) by 3.

`9x+9y=126\ldots\ldots(3)`

Now, subtract equation (1) from (3).

`\begin{gathered} 9x+9y-(-x+9y)=126-36 \\ 9x+9y+x-9y=90 \\ 10x=90 \\ x=(90)/(10)=9 \end{gathered}`

Put x=9 in equation (1) and solve for y.

`\begin{gathered} -9+9y=36 \\ 9y=36+9 \\ 9y=45 \\ y=(45)/(9) \\ y=5 \end{gathered}`

Therefore, x=9 and y=5.