How to Graph Linear Equations Without a Table
A linear equation is a type of equation that makes a line when graphed. This set of equations take the form y = mx + b, where m is the slope and b is the y-intercept. When you solve linear equations by inputting a particular value for X, what you get out is a Y coordinate. The pairs of X and Y coordinates enable you to graph a linear equation without the use of a table.
Instructions
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1
Solve the equation for the first value. For example, if you want to plot Y = 5x + 2 at x={1,2,3...10} then solve for x=1:
Y = 5(1) + 2 = 7
This gives you the X,Y coordinates (1,7). -
2
Plot the value from Step 1 on your graph. For example, to plot the coordinate (1,7), place your finger on the "X" axis of your graph at 7, then move your finger up 1 space (or however many squares on your graph paper represent a vertical unit of one). Place a dot at that point, then write "(1,7)" below the dot.
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3
Solve the equation for the last value. In the example given, the last value is 10, so:
Y = 5(10) + 2 = 52
This gives you the X,Y coordinates (10,52). -
4
Plot the values from Step 3 on your graph.
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Join the two coordinates together with a ruler by drawing a line between the dots at (1,7) and (10,52) with a ruler. This is the graph of your linear equation.
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Tips & Warnings
The equation is a straight line, so you only need two points to draw the line for the equation. However, you may want to calculate three points to double-check your calculations.
References
- Photo Credit math image by jaddingt from Fotolia.com