Verified Answer :

Step \(1\)

Find the length of the side MN

we know that

Applying the Pythagorean Theorem

\(ML^{2} =NL^{2} +MN^{2}\)

Solve for MN

\(MN^{2}=ML^{2} -NL^{2}\)

in this problem

\(ML=25\ units\\ NL=15\ units\)

Substitute in the formula above

\(MN^{2}=25^{2} -15^{2}\)

\(MN^{2}=400\)

\(MN=20\ units\)

Step \(2\)

Find the value of cos (M)

we know that

in the right triangle MNL

\(cos (M)=\frac{adjacent\ side\ angle\ M}{hypotenuse}\)

\(adjacent\ side\ angle\ M=MN=20\ units\\ hypotenuse=ML=25\ units\)

Substitute

\(cos (M)=\frac{20}{25}\)

\(cos (M)=\frac{4}{5}\)

\(cos (M)=0.8\)

therefore

The answer is

The value of cos(M) is equal to \(0.8\)