Take all the variables and put them next to each other but still in order.
Keep their negatives and positives.
6x-2x-9x 5y+3y
Do the math with the variables that way, and you'll get an answer of
-5x 8y
Reform them into the simplified equation, so you'll end up with an equation of
-5x+8y
The x would be before the y since that's how it is in the alphabet. That would be a simplified form of the equation.
