Okay, so to solve this problem we need to see if the equations equal each other on both sides. For example 1+3=7-3 , in this problem we do the math on both sides to get the answer. 1+3=4 and 7-3 =4, so it will be 4=4 which is true. so for your problem you just need to do the math on both sides. and when you do that you get 19=18, this is false or untrue as they clearly don't mathematically.
