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put this solution on YOUR website!Given the equation for an ellipse, find the length of the major axis:

Re-arrange this to the standard form of the equation of an ellipse with major axis on the x-axis:

where a = the semi-major axis and b = the semi-minor axis.

Divide both sides by 12.

Simplify the left side.

Compare with the standard form:

Take the square root of both sides.

This is the length of the semi-major axis.

This is the length of the major axis.