Remark
AKL is an isosceles right triangle. That's because AK = KL = 2 and K is a right angle.
That makes <A = <L = 45o
Since AM = ML (Given) and KM is common to both Triangle AKM and Triangle LKM, the two triangles are congruent by SSS
Since <AKM = <LKM = 90/2 = 45 (Corresponding parts of congruent triangles are congruent) KM is a perpendicular bisector of AL.
So KM = ML because <MKL and <KLM are both = 45 degrees.
If you find one of KM or ML, you have the other.
KM^2 + LM^2 = 2^2 Remember that KM is perpendicular to AL
2KM^2 = 4
KM^2 = 2
sqrt(KM^2) = sqrt(2)
KM = sqrt(2)