Find the constant sum for an ellipse with foci f1 (0, -12), f2 (0, 12) and the point on the ellipse (9, 0).

Step-by-step explanation:

1.

6 * 6 = 36

6 * 6 / 2 = 18

4(18) = 72 (4 triangles)

SA = 36 + 72 = 108 in^2

2.

11 * 4.5 = 49.5

2(49.5) = 99 (2 flaps)

7 * 4.5 = 31.5

2(31.5) = 63 (2 flaps)

11 * 7 = 77

2(77) = 154 (2 flaps)

SA = 99 + 63 + 154 = 316 in^2

3.

25 * 25 = 625

6(625) = 3750 (6 squares)

SA = 3750 ft^2

4.

40 * 60 = 2400

3(2400) = 7200 (3 flaps)

25 * 40 /2 = 500

2(500) = 1000 (2 flaps)

SA = 7200 + 1000 = 8200 cm^2

5.

15 * 9 = 135

3(135) = 405 (3 flaps)

8 * 9 /2 = 36

2(36) = 72 (2 flaps)

SA = 405 + 72 = 477 in^2

6.

9 * 12 = 108

10 * 9 /2 = 45

2(45) = 90 (2 flaps)

12 * 10 /2 = 60

2(60) = 120 (2 flaps)

SA = 108 + 90 + 120 = 318 mm^2