I forgot how to do this, I need an explanation to find the answer

Answer:
23.53
Step-by-step explanation:
OK so we got sin 52°=0.8 and the cos 52°=0.6
but we need tan 52° because we don't want to spend our time on calculating hypothenuse so
[tex] \frac{ \sin(52) }{ \cos(52) } = 1.3 = \tan(52) [/tex]
so
[tex]1.3 = \frac{x}{18.1} = = = > x = 23.53[/tex]