Since the two numbers are in these ( ), you do those first, always.
So you subtract 15-5 which equals 10. 15-5=10
The Dot between the ) and the 2 is another symbol for multiplication. The most well known symbol for Multiplication is ×.
So we have the number 10, you want to do 10 × 2.
10 × 2 = 20.
Don't let the dot fool you
