Hi! Hello!
Not sure if you still need this answer, but I'd love to help you out if you do.
This is an example of the distributive property. Basically, it involves taking the 2 and distributing it to the x and y terms to give you 2x + 2y.
You could think of the distributive property as one-step-up from normal multiplication of two numbers. Think of 2(3). You would carry the two over to give you six.
Now, think of 2(3+3). You could add the threes together and multiply the numbers together, but in the case of x and y, you can't get away with this. You need to carry the two over to each three, giving you 6+6, equalling twelve.
Feel free to ask me any questions about this if you feel the need. Hope this helped you out!
