Data:
Hypotenuse is 7.5
Opposite of angle x is 6
Cosine = Side opposite (S.O) the angle on the hypotenuse (h)
We have:
[tex]Cos (\alpha)x = \frac{S.O}{h} [/tex]
[tex]Cos (\alpha)x = \frac{6}{7.5} [/tex]
[tex]\boxed{Cos (\alpha)x = 0.8}[/tex]
For better understanding, see the annex: