Example

Graphing y=12x+3y = \frac{1}{2}x + 3 by Plotting Points

To graph y=12x+3y = \frac{1}{2}x + 3, apply the Point-Plotting Method while choosing xx-values strategically to avoid fractional results.

Step 1 — Find three solution points. Because the coefficient of xx is 12\frac{1}{2}, select xx-values that are multiples of 22 so that the product 12x\frac{1}{2} \cdot x is a whole number:

  • x=0x = 0: y=12(0)+3=0+3=3y = \frac{1}{2}(0) + 3 = 0 + 3 = 3, giving (0,3)(0, 3)
  • x=2x = 2: y=12(2)+3=1+3=4y = \frac{1}{2}(2) + 3 = 1 + 3 = 4, giving (2,4)(2, 4)
  • x=4x = 4: y=12(4)+3=2+3=5y = \frac{1}{2}(4) + 3 = 2 + 3 = 5, giving (4,5)(4, 5)

Step 2 — Plot the points. Mark (0,3)(0, 3), (2,4)(2, 4), and (4,5)(4, 5) on a rectangular coordinate system. All three points line up, confirming the calculations are correct.

Step 3 — Draw the line. Connect the three points with a straight line, extend it across the grid, and add arrows on both ends. The resulting line is the graph of y=12x+3y = \frac{1}{2}x + 3.

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Updated 2026-04-21

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