Answer
$x \approx 1.9$
Work Step by Step
Use the definition of cosine
$cos (35^o) = Adjacent / Hypotenuse$
$cos (35^o) = 1.575 / x$
Put $cos 35^o$ into a calculator
$cos 35^o \approx 0.81915$
Plug that into the equation
$0.81915 = 1.575/x$
$0.81915/1.575 = 1/x$
$1.575/0.81915 = x$
$x \approx 1.9$ (Rounded to the nearest tenth)