Foundations: Rational Numbers and the Cartesian Plane

Notes

**Rational Numbers** are numbers that can be expressed as the quotient or fraction of two integers, where the numerator (top number) and the denominator (bottom number) are both integers, and the denominator is not zero. Examples include: - \( 5 \) (which can be expressed as \( \frac{5}{1} \)) In a 2D coordinate system (also called the Cartesian plane), there are two axes: 1. **X-axis**: This is the horizontal axis, where the value of X (the first number in a coordinate pair) represents the position left or right from the origin. 2. **Y-axis**: This is the vertical axis, where the value of Y (the second number in a coordinate pair) represents the position up or down from the origin. The intersection of these two axes is called the **origin**, represented by the point (0, 0).