This document provides an overview of linear equations in two variables and the rectangular coordinate system. It defines key terms like the x-axis, y-axis, and quadrants. It describes how René Descartes developed the coordinate plane and revolutionized mathematics. The document explains how to locate and plot points on the plane using x and y coordinates. It includes examples of plotting points and determining the coordinates of points. Students are assigned questions about plotting points in different quadrants and how the signs of coordinates affect a point's location.