We can use SOH CAH TOA to solve this :)
We’re going to use Cosine because the angle and sides given are Adjacent and Hypotenuse- which goes with the CAH part of SOH CAH TOA.
Cos(18) = x/25
Multiply both sides by 25
25cos(18) = X = 23.776
So x = 23.776 cm
I hope this Helps!