To solve this problem you must apply the proccedure shown below: 1. You have that the ellipse given as a vertical major axis (a=13), therefore, taking the ellipse with its center at the origin, you have the following equation: (y^2/a^2)+(x^2/b^2)=1 2. You have the distance from the center of the ellipse to the focus: c=12, therefore, you can calculate the value of b, the minor radius: c^2=a^2-b^2 b=√(13^3-12^2) b=5 3. Therefore, the equation is: a^2=169 b^2=25 (y^2/169)+(x^2/25)=1 The answer is: (y^2/169)+(x^2/25)=1