I became a tutor and idk how to do this

The correct answer is A

Step-by-step explanation:

Move the variable to the right --> -2y=9-x

Change the signs --> 2y=-9+x

Divide both sides --> y= -9/2+ 1/2x

Reader the terms --> y=1/2x+-9/2

y = 1 x - 9 ( L.C.M = 2 )

2 2

1(1x)-1(9)

2

x-9

2

Write down the numbers, one under the other, with the decimal points lined up .Put in zeros so the numbers have the same length (see below for why that is OK) Then add, using column addition, remembering to put the decimal point in the answer.

Step-by-step explanation: