Convert the Celsius (C) temperatures to Fahrenheit (F) if you have only the Celsius temperatures. Use the formula: F = {C x (9/5)} + 32 to convert Celsius to Fahrenheit. For example, 10 C is equivalent to 50 F = {10 x (9/5)} + 32 = {C x (9/5)} + 32. Convert the Fahrenheit (F) temperatures to Celsius (C) if you have only the Fahrenheit temperatures. Use the formula: C = (5/9) x {F - 32} to convert Fahrenheit to Celsius. For example, 140 F is equivalent to 60 C = (5/9) x {140 - 32} = (5/9) x {F - 32}.
Create a table with two columns. Use the first column for the Celsius temperatures, and enter the equivalent Fahrenheit temperatures in the second column. The first column will give the x-value of each data point, while the second column yields the y-value. Each data point you plot on the graph consists of a Celsius (x-value) and a Fahrenheit (y-value) temperature.
Draw a horizontal axis at the bottom of the graph paper using the ruler. Label this axis as Celsius. This is the x-axis of the graph.
Divide the x-axis into intervals that accommodate the range of Celsius data. For example, if your set of Celsius temperatures ranges from 10 to 60 degrees, the x-axis must accommodate a range of 50 degrees. Range is the difference between the highest and lowest values. Divide the x-axis into equally spaced intervals. For example, a 50 degree range could be divided into intervals of 5 degrees, starting at 10 C and ending at 60 C.
Draw a vertical axis on the left side of the graph paper using the ruler. Label this axis as Fahrenheit. This is the y-axis of the graph.
Divide the y-axis into intervals that accommodate the range of Fahrenheit data. For example, if your set of Fahrenheit temperatures ranges from 50 to 140 degrees, the y-axis must accommodate a range of 90 degrees. Divide the y-axis into equally spaced intervals. For example, a 90 degree range can be divided into intervals of 10 degrees, starting at 50 F and ending at 140 F.
Plot all the data points on the graph paper. Use a pencil dot to represent each data point.
Use the ruler to draw a line through the data points. This line represents the mathematical relationship between Celsius temperatures and Fahrenheit temperatures.