Simplify the following text for a Grade 14 native English-speaking person.
Original: The slide rule is used primarily for multiplication and division , and also for `` scientific '' functions such as roots , logarithms and trigonometry , but does not generally perform addition or subtraction .
Simplified: The slide rule is used primarily for multiplication and division , and also for functions such as roots , logarithms and trigonometry , but is not normally used for addition or subtraction .