Scott P. Raffone
The Cartesian coordinate system is arguably the best tool for mathematicians studying Geometry. It is a series of vertical parallel lines that are perpendicular by an infinite number of horizontal parallel lines forming a "grid." The axis that separates the positive vertical lines from the negative vertical line is called the y-axis. The axis that separates the positive horizontal lines from the negative horizontal line is the x-axis. The location where the x-axis and y-axis intersect is called the origin. We name the points (x, y) when they are in coordinate form.
In our problem we are charting the temperature of sauce over a period of time. Our x-values are our independent variable. We will use time and measure the temperature every minute. Our dependent variable, temperature, will be our y-values as the temperature of the water will depend on the time it is measured.