Okay, let's find the perimeter of the triangle MNK. We're given that KN = 40 and KM = 30. Also, MF = FN, and angle MFN is a right angle.
Since MF = FN and EF is perpendicular to MN, we know that EF is the median and altitude of triangle KMN. Therefore, triangle KMN is an isosceles triangle with KM = KN.
However, the problem states KN = 40 and KM = 30, which means the triangle is *not* isosceles. There is likely a typo in the diagram or the problem statement, and the point E is the midpoint of KM.
Let's assume there is a mistake and that EF is the median to KM. Since triangle MNK is a right triangle where the angle at N is 90 degrees and the point F is the midpoint to MN, we know that MF = FN = KE. But since EF is perpendicular to KM, triangle MNK is not a right triangle. Therefore, the statement that MF = FN has to mean that the point E is the midpoint to KM. So we know that KE = EM. So EM = 30 / 2 = 15.
Since EF is a median and altitude of KMN, the triangle KMN is isosceles, and KN = KM. However, the problem statement contradicts this and does not state the triangle KMN is a right triangle. There is something wrong with this problem. Let's assume that there is a typo and angle MNK is a right angle. We will need to find the side MN.
Using the Pythagorean theorem:
$$KM^2 = KN^2 + MN^2$$
$$MN^2 = KM^2 - KN^2$$
$$MN = \sqrt{KM^2 - KN^2}$$
$$MN = \sqrt{30^2 - 40^2}$$
However, since KN > KM, there is no solution.
Let's assume there is a typo and that KM = 40 and KN = 30, and angle N = 90 degrees.
$$KM^2 = KN^2 + MN^2$$
$$MN^2 = KM^2 - KN^2$$
$$MN = \sqrt{KM^2 - KN^2}$$
$$MN = \sqrt{40^2 - 30^2}$$
$$MN = \sqrt{1600 - 900}$$
$$MN = \sqrt{700}$$
$$MN = 10\sqrt{7}$$
Then the perimeter will be KM + KN + MN. Which means that the perimeter is 40 + 30 + 10$\sqrt{7}$ = 70 + 10$\sqrt{7}$ = x
$$P = KM + KN + MN = 40 + 30 + 10\sqrt{7} = 70 + 10\sqrt{7}$$
So, x = 70 + 10$\sqrt{7}$ which is approximately 96.46.
Answer: 70 + 10$\sqrt{7}$