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Hyperbolas with the same pair of foci are said to be confocal. Show that the following equations have confocal hyperbolas for their graphs and sketch them all on the same set of axes.

• [math]x^2 - \frac{y^2}{24} = 1[/math]
• [math]\frac{x^2}{9} - \frac{y^2}{16} = 1[/math]
• [math]\frac{x^2}{16} - \frac{y^2}{9} = 1[/math]
• [math]\frac{x^2}{24} - y^2 = 1[/math].