Help I wish I could have someone’s social media so I can just ask instead of posting questions all the time but!! Help please

18

Step-by-step explanation:

as you see the smaller model is the same shape if you put the small model the same way the big one is you see the small model has a one where the big one has a nine so you times everything by nine because nine times one is 9 so you do that and see that the two is where the x is and times the 2 by nine and thats your answer

The missing side is 18

Step-by-step explanation: If you look you will notice that all the numbers on the figure on the left side are just the numbers on the figure on the right side but times 9.

So i'll just do the same with the 2.

2 x 9 = 18

That's how i did it.

Hope that helps!