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An ellipse with equal radii

Write down the equation of the ellipse shown in the diagram.

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An ellipse-shaped closed curve has centre (h,k). A leftwards horizontal radius and a downwards vertical radius are both labelled r. Use these equal lengths to determine its equation.
An ellipse-shaped closed curve has centre (h,k). A leftwards horizontal radius and a downwards vertical radius are both labelled r. Use these equal lengths to determine its equation.
An ellipse-shaped closed curve has centre (h,k). A leftwards horizontal radius and a downwards vertical radius are both labelled r. Use these equal lengths to determine its equation.

CJC · Lecture · Example 3

Compare the two labelled radius lengths before choosing the denominators.

Read the worked solution