This is pretty simple. This requires the order of operations. So for the order of operations, it basically tells you the order on how you solve operations.
The first order is brackets, the second one is division, the third one is multiplication and the fourth one is addition or subtraction.
For this case, you have { 6-4 }. 6-4 is on brackets, so you have to solve it first. The answer is 2.
After that, you can divide 50 by 2, which gives you 25.
