# 17.5 Graphical Solution of Inequalities with Two Variables

**Points Above and Below Curve • Use of Dashed Curve or Solid Curve • Solution Using Calculator**

To this point, we have considered inequalities with one variable and certain methods of solving them. We may also graphically solve inequalities involving two variables, such as `x` and `y`. In this section, we consider the solution of such inequalities.

Let us consider the function $y\hspace{0.17em}=\hspace{0.17em}f(x)\hspace{0.17em}.\hspace{0.17em}$ We know that the coordinates of points on the graph satisfy the equation $y\hspace{0.17em}=\hspace{0.17em}f(x)\hspace{0.17em}.\hspace{0.17em}$ However, for points above the graph of the function, we have $y\hspace{0.17em}>\hspace{0.17em}f(x)\hspace{0.17em},\hspace{0.17em}$ and for points below the graph of the function, we have $y\hspace{0.17em}<\hspace{0.17em}f(x)\hspace{0.17em}.\hspace{0.17em}$ Consider the following example.

# EXAMPLE 1 Checking points above and below line ...

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