Example

Solving {3x2y6,  y>14x+5}\{3x - 2y \leq 6,\; y > -\frac{1}{4}x + 5\} by Graphing

Solve the system {3x2y6y>14x+5\left\{\begin{array}{l} 3x - 2y \leq 6 \\ y > -\frac{1}{4}x + 5 \end{array}\right. by graphing.

Step 1 — Graph 3x2y63x - 2y \leq 6. The boundary line is 3x2y=63x - 2y = 6. Because the inequality uses \leq (non-strict), draw a solid line. Test (0,0)(0, 0): 3(0)2(0)63(0) - 2(0) \leq 6 gives 060 \leq 6, which is true, so shade the side that contains the origin.

Step 2 — Graph y>14x+5y > -\frac{1}{4}x + 5 on the same grid. The boundary line is y=14x+5y = -\frac{1}{4}x + 5. Because the inequality uses >> (strict), draw a dashed line. Test (0,0)(0, 0): 0>14(0)+50 > -\frac{1}{4}(0) + 5 gives 0>50 > 5, which is false, so shade the side that does not contain the origin.

Step 3 — Identify the solution. The solution is the overlapping shaded region. The intersection point of the boundary lines is not included in the solution because one of the boundary lines is dashed.

Step 4 — Verify with a test point. Choose a test point in the overlapping region and substitute it into both inequalities to confirm both are true.

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Updated 2026-04-28

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