Clive W. Humphris

**MATHEMATICAL RULES: Sign Rules. **

Numbers can have one of two signs, positive (+) or negative (-). The plus or positive sign is assumed if the negative or minus sign is not shown.

There are rules for multiplying and dividing numbers, which must be applied. If the signs of the two numbers are the same then the answer will be positive, and if different the answer will be negative.

Input your values, prefixing each of the four combinations (+) and (+), (-) and (-), (+) and (-) or (-) and (+) of positive and negative signs in turn.

Note. It is considered good practice to enclose negative numbers within parenthesis or brackets. This makes the equation clear when two signs are written next to each other, i.e. 5 × -6 = -30, better to write as 5 × (-6) = (-30).

- Table of Contents
- Interactive eTextbooks
- Number Systems
- Number Conversion
- Number Types
- Compound Measures
- Roots
- Angles and Parallels
- Triangle Ratios
- Triangle Angles
- Percentages
- Ratios
- Fractions
- Vectors
- Geometry
- Circle Angles
- Area
- Surface Area and Symmetry
- Volume
- Laws
- Algebra 0
- Algebra 1
- Algebra 2
- Mathematical Rules
- Powers and Indices
- Simplifying
- Linear Equations
- Graphing
- Slope and Translation
- Curves and Angle Conversion
- Personal Finance
- Data Analysis
- Binary Numbers
- Binary Arithmetic