Subtraction
noun
What's a method to decrease something? Well, you take something away. You do subtraction.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well. Note that the ほう changes to ぽう. This is because you're trying to subtract Polar (ぽう) bears from the area around you as they're very dangerous and you use a cologne made from meat.
先日、加法をマスターしたので今日からは減法を学びます。
I mastered addition the other day, so I will start learning subtraction today.
私の算数で一番得意な分野は減法です。
The area that I am good at most in math is subtraction.
物理の問題で、ベクトル減法はあまり見ませんが、たまに出てくることがあります。
In physics problems, we don’t come across vector subtraction very often, but it does pop up sometimes.